Any idea what this is?
winupd64x.exe
It keeps popping up for me to run program. I don’t know enough about these thing and am afraid to do so but maybe it’s just another update.
Not recommending you use their clean up process, but here http://www.prevx.com/filenames/X678219248043914988-X1/WINUDP64.EXE.html is an explanation of the virus.
NOTE. You mentioned winupd64.exe which is slightly different.
winupd64x.exe
A web search indicates it's a virus.
Here is what you apparently have: A fake antivirus program called “Antivirus.”
Manual steps to get rid of it are here:
http://www.2-spyware.com/remove-antivirus.html