I just had the exact same problem. It just happened to me about an hour ago when a friend plugged in his USB in my laptop and it deleted me all the data from an SD card already plugged in.
I keep getting the same alert... the only different thing is that its located elsewhere on svchost.exe
Also, if I plug in any other USB or external device. It also gets infected. And throws this alert.
Should I do the same thing and erase the file too?
Please help me.