how to fix window 7 black screen?

If you get a black screen instead of your desktop, and you see a mouse arrow, you're running in safe mode. To fix this, close all the apps you opened since the last time you could see your desktop. Then right-click an empty spot on the taskbar, and select "Task Manager.
Fixing the Black Screen of Death Error in Windows 7 and Windows 8 With the Windows Black Screen of Death, I have never figured out how to get it to go away. The only way I have found to resolve the issue is to reboot the computer. In the past when this happened, I was able to go into Task Manager and kill Explorer.
Restart your computer.

Press F8 repeatedly until you see the list of boot options.

Choose Last Known Good Configuration (Advanced)

Press Enter and wait to boot.

Black screen of death (BKSOD) is an error screen to show you when Windows operating system encounter some seriously system errors which can cause the system to shut down due to various of reasons, like system problems, hardware or software problems, etc.