How to fix a Windows 8.1 upgrade that ends with a black screen

After your upgrade to Windows 8.1, if you see a black screen and only a mouse pointer, you may have video drivers that are incompatable.  The solution is to remove the video drivers in safe mode and here is how to do that.

Make sure you boot to the Windows 8.1 DVD or Windows 8.1 thumb drive using UEFI and not legacy boot if you have a PC with UEFI.  On a Dell PC, using F12 will let you choose what to boot to.

Once you have booted from the 8.1 install media (Win8 may work too), look for the repair option.

Then choose Repair + Troubleshoot + Advanced Options + Command Prompt

1.    Open Command Prompt.

2.    With Command Prompt open, execute the correct bcdedit command as shown below based on which Safe Mode option you'd like to start:

Safe Mode:

3.  bcdedit /set {default} safeboot minimal

Safe Mode with Networking:

bcdedit /set {default} safeboot network

Safe Mode with Command Prompt:

bcdedit /set {default} safeboot minimal

bcdedit /set {default} safebootalternateshell yes

Tips: Be sure to type whatever command you choose exactly as shown and then execute it using the Enter key. Spaces are very important! The { and } brackets are the ones above the [ and ] keys on your keyboard. Two separate commands are required to start Safe Mode with Command Prompt so be sure to execute them both.

A properly executed bcdedit command should return a "The operation completed successfully" message.

If you see "The parameter is incorrect", or "The set command specified is not valid", or "...is not recognized as an internal or external command...", or a similar message, check Step 3 again and make sure you executed the command properly. If you get other errors about not finding the BCD, then you might be booting into Legacy Mode, make sure your using UEFI.

4.    Close the Command Prompt window.

5.    In Windows 8, tap or click on Continue.

6.    Wait while your computer restarts.

7.    Once Windows starts, log in as you normally do and use Safe Mode to open the device manager from the control panel and remove all video drivers and check the option to delete the drivers from the PC.
Important: Windows will continue to start in Safe Mode every time you reboot unless you undo what you did in Step 3.

Now that you have removed the drivers, you can change the BCD back from safemode using a CMD.exe windows that should be elevated to Administrator.

Return the BCD to Standard with this command:
bcdedit /deletevalue safeboot

Now reboot and you should be able to login to your PC again.

Make sure you use the drivers supplied by your PC manufacturer first before you try generic video drivers.

For Dell, those will be at http://www.dell.com/support