submit a ticket to Webroot about this error and see if they have a fix.

You can also use DBAN (it's free) to wipe the hard-drive. Then fresh install Windows.

If you prefer to not to wipe the hard-drive by keeping the operating system on it, you can use also the freeware CCleaner Freeware (in case Webroot has no solution or answer yet) to clean-up drive using many passes.