You’re infected—if you want to see your data again, pay us $300 in Bitcoins
You can work to prevent this by creating a group policy that disallows     %AppData%\*.exe 

and     %AppData%\*\*.exe

A good discussion of this happened here: http://www.reddit.com/r/sysadmin/comments/1mizfx/proper_care...sidenote: this virus actually scares me, and it sounds like it actually scares most people who work in IT.  This is the shittiest thing anybody has ever seen, it sounds like.