As you may have noticed, Microsoft has disabled the standard method of accessing Safe Mode in Windows 8 in favor of a new Modern UI system. In other words, you can no longer press F8 during the Windows start up sequence and access the black and white Advanced Boot Options menu system from which you can select Safe Mode. Microsoft's justification for disabling the F8 key is essentially that computers boot up so fast these days that people will have trouble pressing F8 before Windows starts.
To be able to use F8 to get to Safe Mode, in Administrator Command Prompt type the command:
bcdedit /set {default} bootmenupolicy legacyhttp://www.techrepublic.com/photos/boot-windows-8-into-safe-mode/6414603?seq=11