Overcoming "It is being used by another person or program." [closed]
I've successfully used Process Explorer to find out which process has the file open. It saves a reboot that may not fix the problem anyway.
In process explorer: Find > Handle or DLL... then search for the name of the folder/file, then double click one of the search results. It'll select a handle in the main window, which you can right click and close.
Try downloading "Unlocker". Google it and take my words that it doesn't have any worm/spyware/virus. It is pretty cool utility and works great. Give it a try.
Did you try the commandline command OpenFiles
It is built in (XP and above I believe) and has several arguments that can be passed in.