# How to troubleshoot common PC problems in Windows 11: a method and fixes

> Troubleshoot a Windows PC in order: find what changed, rule out the simple causes, then fix no boot, blue screens, no internet, no sound and failed updates.

- URL: https://computese.com/how-to-troubleshoot-common-pc-problems/
- Author: Duong Quan Nguyen, CEO, Computese
- Published: 2024-08-07
- Updated: 2026-09-25
- Topics: IT support

## In short
- Troubleshoot in order: identify the problem and what changed, question the obvious, test one theory at a time, fix with a way back, verify, and write down what you did. That is CompTIA's six-step method, and it works on a home PC too.
- Separate a PC that will not power on (power or hardware) from one that will not start Windows. When start-up fails, Windows opens its Recovery Environment, where you can run Startup Repair, uninstall the latest update or restore.
- Most blue screens come from drivers: Microsoft attributes 70% of the crashes it analyzed to third-party driver code. Note the stop code, undo recent driver or hardware changes, then test memory and system files.
- Back up before any reset. Reset this PC with Keep my files still removes your apps and settings, and on an encrypted PC most recovery tools ask for the BitLocker recovery key.
- Stop and get help when the signs point to failing hardware (clicking drives, a burning smell, crashes that survive a clean reinstall) or when the PC holds files that exist nowhere else.

To troubleshoot a PC problem, write down exactly what happens and what changed just before it started, rule out the simple causes first, then test one fix at a time and keep notes of each change. On Windows 11, the built-in troubleshooters, Safe Mode and the Windows Recovery Environment handle most of what remains.

This guide starts with that method, modelled on the one CompTIA teaches IT support technicians, then applies it to the common failures: a PC that will not turn on or boot, blue screens, no internet, no sound, display and device faults, crashing apps and failed updates. It ends with the last resorts and the point to call a professional. The steps are for Windows 11 as of September 2026; most work on Windows 10 too. A PC that works but is slow is a different job: [diagnose the slowdown by symptom](https://computese.com/how-to-fix-a-slow-computer-practical-tips-2024/), or run the [15-minute speed-up checklist](https://computese.com/how-to-speed-up-a-slow-computer/) first.

## A troubleshooting method anyone can follow

Technicians work through problems in a fixed order, and the version most of them learn comes from CompTIA. The [A+ Core 1 exam objectives (220-1201, V15)](https://lecbyo.files.cmp.optimizely.com/download/34be017cb73211ef8985a6f347fbf652) list six steps. Since V15 the method is printed there as a competency standard rather than a tested objective, and CompTIA recommends it to anyone new to IT support. Translated for a home or office PC:

1. **Identify the problem.** Write down the exact symptom and any error code; a phone photo of the screen is fine. Ask what changed just before: a Windows update, a new app or driver, a new device, a power cut. Try to make it happen again, and take several problems one at a time. [CompTIA's explainer](https://www.comptia.org/en/blog/use-a-troubleshooting-methodology-for-more-efficient-it-support/) lists the same moves: identify symptoms, determine recent changes, duplicate the problem, narrow its scope.
2. **Establish a theory of probable cause, and question the obvious.** Plugged in, switched on, charged, on the right input? Then search the exact error code on the vendor's support site.
3. **Test the theory** without changing anything you cannot undo: move the device to another port or PC, start in Safe Mode, see whether your phone gets online on the same Wi-Fi. If the theory was wrong, go back to step 1.
4. **Plan the fix, then apply it.** Back up whatever the fix could put at risk and know how you would reverse it (CompTIA's guide calls this a rollback plan). Make one change, then test.
5. **Verify full system functionality.** Test the whole task that failed, restart once to confirm the fix holds, and prevent a repeat if you can.
6. **Document findings, actions and outcomes:** symptom, cause, what you changed. It is the first thing a technician asks for, and it tells you what to undo if the fix breaks something else.

Change one thing at a time. If you update a driver, uninstall an app and reset the network in one go, you will not know which change fixed the problem, or which to undo when something new breaks. And know when to stop: a step you do not understand, on a PC that holds the only copy of files you need, is the point to hand over.

> [!IMPORTANT]
> Back up before you change anything. Copy the files you cannot lose to an external drive or cloud storage first. [Microsoft's recovery guide](https://support.microsoft.com/en-us/windows/experience/backup-recovery/recovery-options-in-windows) opens with the same warning, because several recovery options can delete data.

| What you see                                                   | Start with                                  |
| -------------------------------------------------------------- | ------------------------------------------- |
| No lights, no fans, no sound                                   | The PC does not turn on                     |
| A logo, then a restart loop or an Automatic Repair screen      | Windows will not start                      |
| "Your device ran into a problem and needs to restart"          | Blue screen and stop code errors            |
| Wi-Fi connected, but "No Internet"                             | No Wi-Fi or no internet                     |
| Everything works except audio, a screen, a keyboard or a mouse | The sound, display or device section        |
| One program fails, or Windows Update keeps failing             | Apps that crash, or Windows Update failures |

## The PC does not turn on

Three failures look alike from across the room. If nothing happens at all (no lights, no fan, no sound), the problem is power. If lights and fans come on but the screen stays dark or the PC beeps, it is stuck in its firmware (the BIOS or UEFI) and usually has a hardware fault. If a logo appears and then start-up fails, the hardware has done its part and Windows is the problem, covered in the next section. [Microsoft's guide to startup issues](https://learn.microsoft.com/en-us/troubleshoot/windows-client/performance/windows-boot-issues-troubleshooting) draws the same line: the first phase is the firmware's power-on self-test (POST), which ends when the firmware finds a valid system disk.

![A PC's start-up drawn as a chain from the wall socket to a desktop tower, its firmware chip, its drive and a monitor, with the one broken link in the chain shown in orange.](https://computese.com/images/blog/how-to-troubleshoot-common-pc-problems/boot-stages.7e1ab814fe-1536.webp)

*Find the last stage that works: no lights is power, lights without a picture is firmware or hardware, and a logo that never finishes is Windows.*

For a PC that shows no sign of life:

- **Check the chain from the wall.** Test the outlet with a lamp, switch on the power strip, and on a desktop check the switch on the back of the power supply and that the cable is seated at both ends.
- **On a laptop, charge it, then force a restart.** For Surface laptops, [Microsoft's advice](https://support.microsoft.com/en-us/surface/startup/surface-won-t-turn-on-or-start) is to use the charger made for the device for at least 15 minutes, then hold the power button for about 20 seconds. It is a sensible first try on any laptop.
- **Disconnect everything external:** USB drives, SD cards, docks, external monitors. An accessory can stop a PC from starting, and Microsoft's checklists begin here.
- **Look for signs of life.** Microsoft's startup guide suggests checking whether the drive activity light works and whether Num Lock toggles its light; if neither does, start-up is stuck before Windows and there might be a hardware issue. Beeps and blinking light patterns are the firmware reporting a fault, and their meaning differs by manufacturer, so look the pattern up on your PC maker's support site.
- **Rule out the monitor.** On a desktop, a monitor that is off or on the wrong input looks exactly like a dead PC.

If you smell burning, unplug the PC and stop. CompTIA's objectives list a burning smell, capacitor swelling and random shutdowns among the symptoms of failing motherboards and power supplies, and none of them is a home repair.

## Windows will not start, or restarts in a loop

When Windows itself fails, it has its own repair kit: the Windows Recovery Environment (WinRE), a small recovery system installed alongside it. [Microsoft describes the trigger](https://learn.microsoft.com/en-us/windows-hardware/manufacture/desktop/windows-re-troubleshooting-features): the Windows loader sets a flag when start-up begins, and Windows clears it before the sign-in screen. If the flag is still set at the next start, the PC opens WinRE and runs Automatic Repair instead. A power cut during start-up can trigger it too, so one Automatic Repair screen does not prove anything is broken.

If WinRE does not appear, [Microsoft's instructions](https://support.microsoft.com/en-us/windows/experience/backup-recovery/windows-recovery-environment) are to interrupt start-up on purpose: as soon as the logo appears, hold the power button until the PC shuts down. Do that twice, and the third start should show Automatic Repair. While Windows still runs, you can get there from **Settings > System > Recovery > Advanced startup > Restart now**, or by holding Shift while you select **Restart**. If a damaged boot manager keeps WinRE from loading at all, make Windows installation media on another PC (Microsoft's recovery guide asks for a USB drive of at least 8 GB), start from it and select **Repair my PC**.

On Windows 11 version 24H2 build 26100.4700 or later, [quick machine recovery](https://learn.microsoft.com/en-us/windows/configuration/quick-machine-recovery/) adds a step: after repeated failed starts, WinRE goes online and checks Windows Update for a fix Microsoft has published for a widespread boot failure. It is on by default on Home editions and on Pro PCs that no organization manages, and needs a cable or password-protected (WPA or WPA2) Wi-Fi.

If that does not help, or the PC does not have it, start with the least disruptive tool under **Troubleshoot > Advanced options**:

| Tool in WinRE         | What it does                                                                                                                                                                                                                                        | Your files                                                                          |
| --------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| Startup Repair        | Diagnoses and repairs common problems that stop Windows starting; Automatic Repair runs it for you                                                                                                                                                  | Kept                                                                                |
| Uninstall Updates     | [Removes the latest quality update](https://support.microsoft.com/en-us/windows/deployment/updates-lifecycle/how-to-uninstall-a-windows-update); after a feature upgrade, Windows also lets you go back to the previous version for 10 days         | Kept                                                                                |
| Point-in-time restore | Rolls the whole PC back to [an automatic snapshot](https://support.microsoft.com/en-us/windows/experience/backup-recovery/point-time-restore-for-windows) taken about every 24 hours and kept for up to 72 hours; Windows 11 version 24H2 and later | Everything after the snapshot is lost, new files included, except files in OneDrive |
| System Restore        | Rolls system files, drivers, apps and settings back to a restore point                                                                                                                                                                              | Kept                                                                                |
| Startup Settings      | Restarts into Safe Mode, Safe Mode with Networking or low-resolution video                                                                                                                                                                          | Kept                                                                                |
| Reset this PC         | Reinstalls Windows (see the reset section below)                                                                                                                                                                                                    | Your choice                                                                         |

If the trouble began right after an update, uninstall that update first. If it began after you installed a driver or a program, start in Safe Mode and remove it, or use a restore point. Safe Mode loads a limited set of files and drivers, and [if a problem does not happen there](https://support.microsoft.com/en-us/windows/experience/startup-boot/windows-startup-settings), the default settings and basic drivers are not its cause. In **Startup Settings**, press 4 or F4 for Safe Mode, or 5 or F5 for Safe Mode with Networking.

A black screen with only a blinking cursor is different: [the firmware cannot find a boot device](https://support.microsoft.com/en-us/windows/hardware/display-graphics/troubleshooting-blank-screens-in-windows). Remove any USB drive and check the boot order in **UEFI Firmware Settings**. If the system drive is missing from the firmware's list, it may have failed; CompTIA lists "bootable device not found" among the symptoms of a failing drive.

On a drive encrypted with BitLocker, most WinRE tools ask for the 48-digit recovery key. If you use a Microsoft account it may be saved there: open aka.ms/myrecoverykey on another device. [Microsoft Support cannot retrieve or recreate a lost key](https://support.microsoft.com/en-us/windows/security/encryption/find-your-bitlocker-recovery-key), so find yours while the PC still works.

## Blue screen and stop code errors

A stop code error is Windows halting on purpose, because carrying on could corrupt data. You see "Your device ran into a problem and needs to restart" with a stop code such as PAGE_FAULT_IN_NONPAGED_AREA or MEMORY_MANAGEMENT, and sometimes the name of the driver file that was running. On Windows 11 version 24H2 and later [the screen is black rather than blue](https://support.microsoft.com/en-us/windows/experience/performance-optimization/troubleshooting-windows-unexpected-restarts-and-stop-code-errors), but it is the same error. Photograph it. One crash that does not come back usually needs no action.

Drivers are the usual suspect. In [Microsoft's analysis of crash root causes](https://learn.microsoft.com/en-us/troubleshoot/windows-client/performance/stop-code-error-troubleshooting), 70% came from third-party driver code, 10% from hardware and 5% from Microsoft code; the other 15% could not be analyzed because memory was too corrupted. If the same stop code keeps returning:

1. **Undo the last change.** Remove hardware added before the crashes began. If a driver was updated, open it in Device Manager, then **Properties > Driver > [Roll Back Driver](https://support.microsoft.com/en-us/windows/update-drivers-through-device-manager-in-windows-ec62f46c-ff14-c91d-eead-d7126dc1f7b6)**.
2. **Start in Safe Mode** if Windows crashes before you can work.
3. **Check Device Manager** for devices marked with an exclamation point, and update, disable or uninstall them.
4. **Free up space:** Microsoft suggests keeping 10% to 15% of the drive free. Then install the latest Windows updates, and firmware updates from your PC maker.
5. **Test the memory.** Press Windows + R, run `mdsched` and select **Restart now and check for problems**. [Windows Memory Diagnostic](https://support.microsoft.com/en-us/windows/experience/performance-optimization/how-to-fix-error-0xa-irql-not-less-or-equal) runs its Standard tests during the restart (press F1 for Extended ones) and shows the result after you sign in.
6. **Repair system files and the disk** from a Command Prompt run as administrator, DISM first, then SFC:

   ```bat
   DISM.exe /Online /Cleanup-image /Restorehealth
   sfc /scannow
   chkdsk C: /f /r
   ```

The [System File Checker](https://support.microsoft.com/en-us/windows/experience/backup-recovery/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system-files) reports whether it found and repaired corrupted files. On the system drive, `chkdsk /f /r` runs at the next restart; let it.

Some stop codes point straight at a component. From Microsoft's list of common ones:

| Stop code                                                                   | Where to look                                                                   |
| --------------------------------------------------------------------------- | ------------------------------------------------------------------------------- |
| VIDEO_TDR_TIMEOUT_DETECTED (0x117) or VIDEO_ENGINE_TIMEOUT_DETECTED (0x141) | The display driver: get the current one from the graphics card's maker          |
| IRQL_NOT_LESS_OR_EQUAL (0xA)                                                | A faulty or outdated driver, or the memory: update drivers, run the memory test |
| DRIVER_IRQL_NOT_LESS_OR_EQUAL (0xD1)                                        | A driver, often the network driver: update it                                   |
| PAGE_FAULT_IN_NONPAGED_AREA (0x50)                                          | The driver named on the screen, then the disk: update the driver, run chkdsk    |
| NTFS_FILE_SYSTEM (0x24)                                                     | File system corruption or bad sectors: run the drive maker's diagnostics        |
| KMODE_EXCEPTION_NOT_HANDLED (0x1E)                                          | A recently added driver: disable or remove it, from Safe Mode if needed         |
| DPC_WATCHDOG_VIOLATION (0x133)                                              | A driver that does not finish its work in time, or incompatible new hardware    |

Windows also writes a memory dump (small ones go to `C:\Windows\Minidump`) that a technician can open in WinDbg to find the faulting driver. Driver Verifier, which stress-tests suspect drivers, is a technician's tool too: Microsoft warns it can slow the PC and cause more crashes while it runs.

## No Wi-Fi or no internet

Find out which link is broken before changing settings. [Microsoft's Wi-Fi guide](https://support.microsoft.com/en-us/windows/experience/connectivity-networking/fix-wi-fi-connection-issues-in-windows) suggests connecting another laptop or phone to the same network: if it gets online, the problem is on your PC; if nothing does, look at the router, the modem or your provider.

![A laptop and a phone share one Wi-Fi router, which connects through a modem to the internet. The phone's link ends in a check mark; the laptop's broken link is shown in orange.](https://computese.com/images/blog/how-to-troubleshoot-common-pc-problems/wifi-split.d92abf8936-1536.webp)

*One test splits the problem in two: if the phone gets online through the same router, the fault is on the PC.*

"No Internet" under a connected network is precise: Windows sends a small web request to a server online, and no answer came back. The PC reached your local network but not the internet. Work through these in order, testing after each:

1. **Run the Network and Internet troubleshooter:** open the Get Help app and search for "connect to network and internet". [Get Help's troubleshooters](https://support.microsoft.com/en-us/support/get-help/windows-troubleshooters) also cover audio, Bluetooth, cameras, printers and Windows Update.
2. **Check the basics:** Wi-Fi on, Airplane mode off, and any physical wireless switch on the laptop on.
3. **Forget the network and reconnect** from **Settings > Network & internet > Wi-Fi > Manage known networks**.
4. **Restart the modem and router.** Unplug both, wait at least 30 seconds, plug in the modem first and wait for its lights to settle, then the router.
5. **Try the other band.** Many routers broadcast separate 2.4 GHz and 5 GHz networks.
6. **Reset the TCP/IP stack and DNS cache** from a Command Prompt run as administrator:

   ```bat
   netsh winsock reset
   netsh int ip reset
   ipconfig /release
   ipconfig /renew
   ipconfig /flushdns
   ```

7. **Reinstall the network adapter driver.** Download the driver from your PC maker first (on another PC if needed), then uninstall the adapter under **Network adapters** in Device Manager and restart.
8. **Use network reset last:** **Settings > Network & internet > Advanced network settings > Network reset**. It removes and reinstalls every network adapter with default settings, so VPN software may need setting up again, and known networks may return with a public profile.

Two readings from `ipconfig` narrow things down. An address starting with 169.254 means Windows got no address from the router, so check that the router's DHCP service is on. And `ping` followed by the **Default gateway** address tests the link to the router: if it replies, the problem lies beyond it, at the modem or the provider.

## No sound

Start with where the sound is going, then work down to the driver, in [Microsoft's order](https://support.microsoft.com/en-us/windows/hardware/audio/fix-sound-or-audio-problems-in-windows):

1. **Check the output device.** Select the speaker icon on the taskbar, then the arrow beside the volume slider, and choose the speakers or headphones you expect. An external monitor without speakers, set as the default output, plays nothing.
2. **Check the hardware and volume:** cables in the right jack (on many PCs green is output, pink the microphone), speakers on, nothing muted, the app's own volume up. Plugged-in headphones can silence the speakers.
3. **Run the audio troubleshooter** in Get Help, or from **Settings > System > Troubleshoot > Other troubleshooters**.
4. **Turn off audio enhancements:** **Settings > System > Sound**, select the device, and set **Audio enhancements** to Off.
5. **Update, reinstall or roll back the audio driver** under **Sound, video and game controllers** in Device Manager. Uninstalling it and restarting makes Windows reinstall it; if audio stopped after an update, roll it back. Windows also has a generic High Definition Audio Device driver.
6. **Restart the audio services:** in Services, restart **Windows Audio** and **Windows Audio Endpoint Builder**.

## Display problems and a second monitor

A black or frozen screen is not always a dead one. Microsoft's [blank screen guide](https://support.microsoft.com/en-us/windows/hardware/display-graphics/troubleshooting-blank-screens-in-windows) starts with the keyboard:

- **Windows logo key + Ctrl + Shift + B** resets the graphics driver; a beep or a flicker means it worked.
- **Windows logo key + P** cycles the display modes (PC screen only, Duplicate, Extend), which rescues a picture sent to a screen that is not there.
- **A black screen with a mouse pointer** usually means Windows Explorer has stopped: press Ctrl + Shift + Esc and restart Windows Explorer in Task Manager.

Then check the cable at both ends, try another cable or monitor, and look under **Display adapters** in Device Manager. If it lists [Microsoft Basic Display Adapter](https://support.microsoft.com/en-us/windows/hardware/display-graphics/microsoft-basic-display-adapter-in-windows), Windows is using its generic driver, which limits resolution and multi-monitor support; install the graphics maker's driver. If the screen broke after a driver update, roll the driver back from Safe Mode, and use the low-resolution video option in Startup Settings when a bad setting leaves no usable picture.

A second screen that shows "No signal", duplicates the first or never appears has its own causes: ports, cables, adapters and the graphics chip's display limit. Our guide to [setting up dual monitors](https://computese.com/how-to-set-up-dual-monitors-on-your-pc/) covers them in a table of symptoms and fixes.

## Keyboard, mouse or USB devices stop working

Test the device before you test Windows. [Microsoft's checklist](https://support.microsoft.com/en-us/windows/hardware/input-devices/mouse-and-keyboard-problems-in-windows):

- Unplug the device, wait a moment for Windows to unload its driver, and plug it back in.
- Try a different USB port. If a USB hub sits in between, make sure it has power, or plug the device straight into the PC.
- Check the cable for damage, the batteries or charge, and the keys and sensor for dirt.
- On a wireless device, press its reset button, or unplug the USB receiver for about 10 seconds. For Bluetooth, run the Bluetooth troubleshooter in Get Help.
- **Try it on another PC.** If it fails there too, the device is faulty.

If it works elsewhere, the problem is on your PC. Look in Device Manager for an exclamation mark on the device or under **Universal Serial Bus controllers**, check Windows Update for drivers, and roll back a driver that changed recently. When every USB port stops at once, restart before anything else. The [A+ Core 2 objectives](https://lecbyo.files.cmp.optimizely.com/download/cefedfb2b8a511ef809306d06d323538) list USB controller resource warnings among common Windows problems, so the fault can be in Windows rather than the device.

## Apps crash or will not open

When one app fails, fix the app. When several fail, or Windows features fail with them, look at Windows.

1. **Update the app and Windows**, then restart.
2. **Repair or reset it.** In [Settings > Apps > Installed apps](https://support.microsoft.com/en-us/windows/apps/repair-apps-and-programs-in-windows), select the three dots beside the app, then **Advanced options > Repair**; if that is missing or does not help, select **Reset**. Desktop programs have **Repair** or **Change** in Control Panel's **Programs and Features**.
3. **Reinstall it.** For an older program, run the Program Compatibility troubleshooter in Get Help.
4. **Rule out other software with a clean boot.** A [clean boot](https://support.microsoft.com/en-us/windows/experience/startup-boot/how-to-perform-a-clean-boot-in-windows) starts Windows with only Microsoft services and no startup apps: in System Configuration (`msconfig`) select **Hide all Microsoft services** and **Disable all**, then disable the startup apps in Task Manager. If the app works now, something else was interfering. Turn the items back on half at a time, as Microsoft suggests, so each restart halves the suspects.
5. **Repair Windows files** with DISM and `sfc /scannow`, as in the blue screen section, when the crashes are not limited to one program.

## Windows Update keeps failing

Run the Windows Update troubleshooter (**Settings > System > Troubleshoot > Other troubleshooters**), then work through [Microsoft's general steps](https://support.microsoft.com/en-us/windows/deployment/updates-lifecycle/troubleshoot-problems-updating-windows):

- **Power and network:** plug the PC in and use a stable connection.
- **Administrator rights:** some updates need an administrator account.
- **External hardware:** disconnect drives, docks and anything else not needed.
- **Free space:** an upgrade needs at least 16 GB free on a 32-bit system or 20 GB on a 64-bit one.
- **Date and time:** turn on **Set time automatically** and **Set time zone automatically**.
- **Update cache:** in `services.msc` stop **Windows Update**, delete the contents of `C:\Windows\SoftwareDistribution`, then start the service again.

The error code tells you where to look. 0x800f0922 means too little disk space or trouble with components such as the .NET Framework; 0xC1900101 points to an incompatible driver, and Microsoft's fix starts with the network and graphics drivers; 0x8007000d means corrupted files in the update cache.

When damaged system files are the cause, Windows 11 can reinstall itself in place: **Settings > System > Recovery > Fix problems using Windows Update > Reinstall now**. [It reinstalls your current version](https://support.microsoft.com/en-us/windows/deployment/install-upgrade/fix-issues-by-reinstalling-the-current-version-of-windows) and keeps your apps, files and settings. It needs Windows 11 version 22H2 with the February 2024 optional update or later, and may be unavailable on PCs a work or school manages. If updates fail for no reason you can find, scan for malware: CompTIA's Core 2 objectives list OS update failures among the symptoms of a PC security problem, and our guide to [antivirus on Windows 11](https://computese.com/choose-the-right-antivirus-software-for-your-pc/) covers what Microsoft Defender already does. For keeping updates flowing in the first place, see [how to keep your computer updated](https://computese.com/how-to-update-your-computer-or-phone/).

## Reset this PC: the last software fix

When the problem is Windows and nothing smaller has worked, [Reset this PC](https://support.microsoft.com/en-us/windows/experience/backup-recovery/reset-your-pc) reinstalls it. Start it from **Settings > System > Recovery > Reset PC**, or in WinRE from **Troubleshoot > Reset this PC**, and make two choices:

| Choice            | What it does                                                                                        |
| ----------------- | --------------------------------------------------------------------------------------------------- |
| Keep my files     | Reinstalls Windows and keeps documents, photos and other personal files; removes apps and settings  |
| Remove everything | Reinstalls Windows and removes files, apps and settings; with **Clean data**, also cleans the drive |
| Cloud download    | Downloads a fresh copy of Windows with current updates; useful when local files are damaged         |
| Local reinstall   | Uses the files already on the PC; faster on a slow connection, but may lack the latest updates      |

Keep my files is the choice people misread. It keeps your files, not your programs: every app you installed has to be reinstalled and signed into again, so list them, with their licence keys, before you start.

![A drive drawn in three layers during Reset this PC with Keep my files: the personal files are lifted out into an orange folder and returned, the apps drop away, and Windows is replaced.](https://computese.com/images/blog/how-to-troubleshoot-common-pc-problems/reset-keep.d6bc5a83ad-1536.webp)

*Keep my files keeps your documents, not your apps: plan to reinstall every program and sign in again.*

> [!WARNING]
> Back up your files before any reset, even with Keep my files, and have your BitLocker recovery key ready. [Windows Backup](https://support.microsoft.com/en-us/windows/experience/backup-recovery/back-up-and-restore-with-windows-backup) can sync your Desktop, Documents, Pictures, Videos and Music folders to OneDrive (a free Microsoft account includes 5 GB), or you can copy them to an external drive.

During a reset the screen can stay black for a long time, occasionally more than 15 minutes, and the PC may restart by itself; restarting it yourself can make the reset fail. Microsoft puts a typical recovery at 30 minutes to 2 hours. Remove everything with Clean data is meant for selling or giving away a PC, and Microsoft notes it does not meet government or industry data erasure standards. After a reset, the steps in [how to set up Windows 11 on a new computer](https://computese.com/how-to-set-up-windows-for-a-new-computer/) apply as if the PC were new.

## When to stop and call a professional

Software cannot repair hardware. The A+ Core 1 objectives list the symptoms technicians treat as hardware faults; these are the ones you can notice at home:

- **The drive:** grinding or clicking noises, a S.M.A.R.T. failure warning, "bootable device not found", very slow reads and writes, missing drives, data loss or corruption.
- **The motherboard, memory or power supply:** POST beeps, no power, a burning smell, swollen capacitors, overheating, random shutdowns, a system clock that will not stay correct.
- **A laptop battery** that has swollen. Stop using and charging it.
- **Crashes that survive a clean reinstall.** If Remove everything did not stop the blue screens, suspect hardware or firmware.

Overheating is sometimes only dust: see [how to clean computer hardware safely](https://computese.com/how-to-safely-clean-your-computers-hardware/) before assuming a part has failed.

Stop early, too, when the PC holds files you have no other copy of. `chkdsk /f /r` and every reset option write to the drive, so a failing drive with irreplaceable data needs its files copied off first, by someone with the tools to do it. Our guide to [recovering deleted files in Windows](https://computese.com/how-to-recover-deleted-files-on-windows/) explains what you can do yourself and when a data recovery service is worth the cost.

For a business, the method is the same, but the notes matter more. Our [IT support](https://computese.com/services/it-support/) provides help by email, Monday to Friday, 9:00 to 17:00 ET, and remote fixes with a note of what was changed; remote sessions happen only with your consent. Recurring issues are traced to their cause and fixed at the root, rather than reset again next week.

## Key terms
- **POST (power-on self-test)**: The checks a PC's firmware runs on its own hardware as soon as it is switched on, before Windows loads. Beeps or blinking lights at this stage report a hardware fault.
- **Windows Recovery Environment (WinRE)**: A small recovery system installed alongside Windows. It opens by itself when start-up fails and holds Startup Repair, Uninstall Updates, System Restore, Startup Settings and Reset this PC.
- **Safe Mode**: Windows started with a limited set of files and drivers. If a problem disappears in Safe Mode, the default settings and basic drivers are not its cause.
- **Stop code (bug check)**: The error name Windows shows when it halts to protect itself, such as MEMORY_MANAGEMENT. The screen is blue on older versions and black on Windows 11 version 24H2 and later.
- **Device driver**: The software that lets Windows talk to a piece of hardware. Microsoft's crash analysis attributes most stop code errors to third-party drivers.
- **SFC and DISM**: Built-in repair tools. DISM fetches healthy Windows components, from Windows Update by default; SFC (sfc /scannow) then checks protected system files and replaces corrupted ones.
- **Clean boot**: Starting Windows with only Microsoft services and no startup apps, then turning the rest back on in halves to find the program that causes a problem.
- **Network reset**: A Windows setting that removes every network adapter and its settings, then reinstalls them with defaults after a restart. Microsoft lists it as the last network fix to try.
- **Reset this PC**: Reinstalls Windows from files on the PC or from a cloud download. Keep my files preserves personal files but removes apps and settings; Remove everything erases the files too.
- **BitLocker recovery key**: A 48-digit number that unlocks an encrypted Windows drive when it cannot unlock itself. Recovery tools often ask for it, and Microsoft Support cannot retrieve a lost one.

## Common questions

### What should I do first when my computer won't boot?

Work out how far it gets. No lights or fans means a power problem: check the outlet, cable and charger, and unplug every accessory. If it shows a logo and then fails or loops, let Windows open its Recovery Environment and try Startup Repair or uninstalling the latest update before anything drastic.

### How do I fix a blue screen error in Windows 11?

Photograph the stop code, then undo whatever changed last: remove new hardware, roll back a recently updated driver, uninstall a new app. Install Windows updates, keep 10 to 15% of the drive free, and run Windows Memory Diagnostic and sfc /scannow. A single crash that does not come back usually needs no action.

### Why does Windows say No Internet when Wi-Fi is connected?

The PC reached your router but not the internet: Windows checks by sending a small web request to a server online. Check whether other devices are online, restart the modem and router, and if the PC's address starts with 169.254 it never got one from the router. Network reset is the last step, not the first.

### Does Reset this PC delete my files?

Only if you choose Remove everything. Keep my files reinstalls Windows and preserves your documents and photos, but it removes your apps and settings, so you reinstall programs afterwards. Back up first either way, and have your BitLocker recovery key ready.

### What are the steps of the CompTIA troubleshooting methodology?

Identify the problem; establish a theory of probable cause, questioning the obvious; test the theory; establish a plan of action and implement the solution; verify full system functionality and add preventive measures; document findings, actions and outcomes. It is printed in the A+ 220-1201 exam objectives, and most CompTIA certifications carry a version of it.

### When should I take my PC to a professional?

When the symptoms point to hardware (clicking or grinding from a drive, a burning smell, swelling, random shutdowns or crashes that continue after a clean reinstall), or when the PC holds files you have no other copy of. In that second case, stop running repair tools on the drive and get the data copied off first.

## Sources
1. [CompTIA A+ Core 1 (220-1201) V15 Certification Exam Objectives](https://lecbyo.files.cmp.optimizely.com/download/34be017cb73211ef8985a6f347fbf652), CompTIA
2. [Use a Troubleshooting Methodology for More Efficient IT Support](https://www.comptia.org/en/blog/use-a-troubleshooting-methodology-for-more-efficient-it-support/), CompTIA
3. [Recovery options in Windows](https://support.microsoft.com/en-us/windows/experience/backup-recovery/recovery-options-in-windows), Microsoft Support
4. [Advanced troubleshooting for Windows startup issues](https://learn.microsoft.com/en-us/troubleshoot/windows-client/performance/windows-boot-issues-troubleshooting), Microsoft Learn
5. [Surface won't turn on or start](https://support.microsoft.com/en-us/surface/startup/surface-won-t-turn-on-or-start), Microsoft Support
6. [Windows RE troubleshooting features](https://learn.microsoft.com/en-us/windows-hardware/manufacture/desktop/windows-re-troubleshooting-features), Microsoft Learn
7. [Windows recovery environment](https://support.microsoft.com/en-us/windows/experience/backup-recovery/windows-recovery-environment), Microsoft Support
8. [Quick machine recovery](https://learn.microsoft.com/en-us/windows/configuration/quick-machine-recovery/), Microsoft Learn
9. [How to uninstall a Windows update](https://support.microsoft.com/en-us/windows/deployment/updates-lifecycle/how-to-uninstall-a-windows-update), Microsoft Support
10. [Point-in-time restore for Windows](https://support.microsoft.com/en-us/windows/experience/backup-recovery/point-time-restore-for-windows), Microsoft Support
11. [Windows startup settings](https://support.microsoft.com/en-us/windows/experience/startup-boot/windows-startup-settings), Microsoft Support
12. [Troubleshooting blank screens in Windows](https://support.microsoft.com/en-us/windows/hardware/display-graphics/troubleshooting-blank-screens-in-windows), Microsoft Support
13. [Find your BitLocker recovery key](https://support.microsoft.com/en-us/windows/security/encryption/find-your-bitlocker-recovery-key), Microsoft Support
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18. [Use the System File Checker tool to repair missing or corrupted system files](https://support.microsoft.com/en-us/windows/experience/backup-recovery/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system-files), Microsoft Support
19. [Fix Wi-Fi connection issues in Windows](https://support.microsoft.com/en-us/windows/experience/connectivity-networking/fix-wi-fi-connection-issues-in-windows), Microsoft Support
20. [Windows troubleshooters](https://support.microsoft.com/en-us/support/get-help/windows-troubleshooters), Microsoft Support
21. [Fix sound or audio problems in Windows](https://support.microsoft.com/en-us/windows/hardware/audio/fix-sound-or-audio-problems-in-windows), Microsoft Support
22. [Microsoft Basic Display Adapter in Windows](https://support.microsoft.com/en-us/windows/hardware/display-graphics/microsoft-basic-display-adapter-in-windows), Microsoft Support
23. [Mouse and keyboard problems in Windows](https://support.microsoft.com/en-us/windows/hardware/input-devices/mouse-and-keyboard-problems-in-windows), Microsoft Support
24. [CompTIA A+ Core 2 (220-1202) V15 Certification Exam Objectives](https://lecbyo.files.cmp.optimizely.com/download/cefedfb2b8a511ef809306d06d323538), CompTIA
25. [Repair apps and programs in Windows](https://support.microsoft.com/en-us/windows/apps/repair-apps-and-programs-in-windows), Microsoft Support
26. [How to perform a clean boot in Windows](https://support.microsoft.com/en-us/windows/experience/startup-boot/how-to-perform-a-clean-boot-in-windows), Microsoft Support
27. [Troubleshoot problems updating Windows](https://support.microsoft.com/en-us/windows/deployment/updates-lifecycle/troubleshoot-problems-updating-windows), Microsoft Support
28. [Fix issues by reinstalling the current version of Windows](https://support.microsoft.com/en-us/windows/deployment/install-upgrade/fix-issues-by-reinstalling-the-current-version-of-windows), Microsoft Support
29. [Reset your PC](https://support.microsoft.com/en-us/windows/experience/backup-recovery/reset-your-pc), Microsoft Support
30. [Back up and restore with Windows Backup](https://support.microsoft.com/en-us/windows/experience/backup-recovery/back-up-and-restore-with-windows-backup), Microsoft Support