How to Fix Blue or Black Screen (BSOD) Errors in Windows

First identify what the screen actually shows. A stop code and an automatic restart point to a Windows crash. A blank display, a mouse pointer on an otherwise empty desktop, and a monitor reporting “No signal” need different checks. The screen colour alone does not distinguish them.

1. Choose the branch that matches your screen

2. Capture a stop code before changing anything

Photograph the error if it stays visible. Keep the exact code, any file named on screen, the time, and what you were doing. Also record whether this started after a driver, update, application or hardware change. Repeated failures during the same task are more useful evidence than a list of unrelated error messages.

If Windows starts but reboots before you can read the next crash, open Advanced system settings > Advanced > Startup and Recovery > Settings. Note the original state of Automatically restart, then clear it temporarily. This changes what happens after a failure; it does not repair the failure. Restore your previous setting after collecting the evidence.

In Event Viewer, inspect Windows Logs > System around the recorded time. Microsoft's Event ID 41 guidance distinguishes a recorded bug check from other unclean shutdowns. A zero bug-check value does not rule out a crash: Windows may have lost power or been unable to write the evidence.

3. If the display is blank, test the display path first

1. Check the monitor's input selection and cable. For a laptop, disconnect a dock or external display and test the built-in panel; for a desktop, try a known-working cable/display.
2. If Windows appears to be running, press Win + Ctrl + Shift + B once. A beep or flicker can accompany the graphics reset. Record whether the picture returns.
3. If an external screen was recently disconnected, use Win + P to check projection mode when you can see the choices. Avoid repeatedly cycling modes without knowing which display is active.
4. Try Ctrl + Alt + Del. If the security screen appears, open Task Manager and restart Windows Explorer. If Explorer is absent, use its Run new task control and enter explorer.exe.

If the desktop returns, save work and test a normal restart. A recovered picture narrows the investigation but does not establish why the screen went blank. If the fault followed a graphics-driver change, record the installed driver version before considering a rollback.

4. Use Startup Settings when normal startup is unreliable

If the sign-in screen or Start menu works, hold Shift while selecting Power > Restart to enter Windows Recovery Environment. If Windows cannot reach either, use Microsoft's linked recovery-access instructions or matching recovery media. Do not keep interrupting an update or firmware installation to force recovery.

In recovery, select Troubleshoot > Advanced options > Startup Settings > Restart. For a repeated crash/restart loop, choose 9 / F9 to disable automatic restart for that startup. To investigate with a minimal driver set, choose 4 / F4 for Safe Mode instead. Select the option needed for your diagnosis; do not disable driver-signature or early anti-malware protection.

Safe Mode working while normal startup fails helps narrow the next test. It is not a guarantee that all hardware is healthy. Restart normally after the check and record whether the same symptom returns.

5. Make one relevant change, then verify it

If recovery requires System Restore, first review what programs would be affected and whether a suitable restore point exists. See the Windows 10 restore-point guide for that separate decision. Avoid stacking firmware updates, registry edits and driver removals into one attempt: if something changes, you need to know which action changed it.

For a technician or administrator, provide the Windows version/build, device model, exact symptom or stop code, crash time, recent changes and results of the checks above. Share crash dumps only through a trusted support channel because they can contain private information. Stop DIY repair if a drive is failing, important data is not backed up, or the PC shows a physical power or battery fault.

Documentation review: 9 October 2026. Revised against Microsoft's diagnostic and recovery documentation. Screenshots and the Event ID example are attributed documentation; no crash was induced and no device repair is claimed.

Microsoft references

Microsoft — Unexpected restarts and stop codesCrash symptoms and initial investigation Microsoft — Troubleshooting blank screensDisplay output, Explorer and graphics-driver checks Microsoft Learn — Interpret Event ID 41Why an unclean shutdown is not a root-cause diagnosis Microsoft — Windows Startup SettingsSafe Mode, restart behaviour and recovery-key prerequisites Microsoft — Access Windows Recovery EnvironmentChoose an access method that fits the available screen