|I'm not sure if this is a permissions issue or a "this process is being used" issue, but I think that either way, restarting your machine into safe-mode, logging in as administrator, and manually removing the file would work.|
Another, easier approach to this would be renaming the file, renaming the folder that the file is in, restarting the machine and then trying to delete it. That might now work, but it could be worth a try.
To start up the computer into Safe-mode, shutdown the computer, turn the computer back on and, before windows starts, continually press f8 until a black and white menu come up. When in the menu, select safe-mode and, once the comptuer starts up, log in as administrator. Locate the file, delete it, and restart the machine normally.
Hope this helps!