I have googled this error and they were from 2009 or so, and they had me type in services and make sure shadow something was on automatic and also system restore. But I didn't have a system restore. They also said something about an administrator, but I was. There was just a list of things to check and uncheck so I did.
I have run scannow, but I am not sure what you mean from a command prompt. I just did it from a regular boot.