There is some controversy over whether you have to disable your anti-virus software to go to a new Microsoft operating system.
Today I updated a Toshiba satellite from Windows 8.0 to 8.1. I had gotten two contradictory tweets from Webroot as to whether it was necessary. I did not disable it. After the two hour procedure. the Action Center told me that Webroot was turned off, as was Windows Defender.
I tried to turn them both on from the Action Center. Windows would intercept Webroot in the usual fashion, but the Action Center was unresponsive. Nevertheless, when I checked the Webroot icon, Webroot said it was on. I ran the scan, and it took longer than it had in 8.0.
Later, Windows defender also insisted on running its own scan. Both scans were clean. In time, the Action Center message went away.
The Webroot told me that it found an occurrence of vssvc.exe and wanted to remove it from the startup menu. It gave me 60 minutes to stop it from doing so.
I let it go ahead and do so.
But then the cold boot failed. I'll provide more details soon.
I don't think this had anything to do with vssvc.exe, which is used for "shadow copy", link. .