Black screen after Windows update.

[rmwright]

After windows update my screen appeared to freeze so I switched off and restarted only to get a completely blank black screen with a small dash symbol in top lefthand corner.
What can I do to recover my PC. Can't perform any actions via the screen and don't know what keys to use to access menu etc. please help.

 

[plodr]

I've read KB 3097877 can cause issues.
If you get on in safe mode, see if that update was installed.