My windows 8.1 pro is dead now after I installed many updates. I don’t which one is causing the error but now the computer screen keep flickering after I log on and there are no application icons being loaded in the task bar; my mouse keeps “loading”. I have tried to do a system restore on several restored points but all emit the same error saying that “System Restore could not access a file. This is probably because an anti-virus program is running on the computer. Temporary disable your anti-virus program and retry system restore…(0x80070005)” I think this probably has nothing to do with AV engines at all. I have chosen System Image Recovery and access my drive where I installed the AV engines and changed their folder names which in turn disables any of its components being loaded by the system from startup. Also I've tried choosing Startup Repair. Yet the system responds it can’t be fixed right now. I then tried out Startup Settings to enter safe mode but I got the original black flickering screen without icons except a blank task bar. Symptom summary: Windows is Bootable, log-on screen is displayed but after logging on, I only see an empty task bar and the whole screen flicker repeatedly. Resetting the windows to the original state using Recovery Tools (Shift+F8 or Shift+Restart) fails. Windows Restore fails, system image recovery fails. It takes too much time to resolve things like this. Good news is I've almost done my homework and save things in drive D that is not where windows 8.1 pro is installed. Could you guide me to resolve this issue ? Thank you everyone.