Ever had such an annoying message given by Windows?
It has many other flavors:
Cannot delete file: Access is denied
There has been a sharing violation.
The source or destination file may be in use.
The file is in use by another program or user.
Make sure the disk is not full or write-protected and that the file is not currently in use.
Now you have an option to unlock it using Unlocker. Now, sometimes it’s theoretically impossible to unlock all files, especially some DLLs that are burned into Windows, but for most applications that you run that are not part of Windows, you either have the choice of unlock, rename, and move. This program is free too and it tries to do it without actually killing processes.