How to remove wfv2.tmp file from Temp folder?

You should be able to delete it in safe mode

If that would not work would also try unlocker - install unlocker and then right click on the folder and choose unlock all - this works in safe mode also
UNLOCKER 1.8.8 BY CEDRICK 'NITCH' COLLOMB (http://ccollomb.free.fr/unlocker/)