The volume for a file has been externally altered so that the opened file is no longer valid?

"The volume for a file has been externally altered so that the opened file is no longer valid."

This error shows up when ever I try to open my Lenovo all in one PC I got in 2012. It has the simple error message and then a black background. When I try to delete the error by clicking the x, it just pops back up again. If you keep pressing x for maybe 20-30 times, the message goes away but the black backdrop stays and I can't use my PC. I just need to extract some old files from it, so I don't mind if it isn't a perfect fix. Please help.

Thanks!

P.S. The "file" in the error is my wacom pen display tablet driver.