Unlocker Software
An unlocker is a utility used to determine what process is locking a file, and displays a list of processes as well as choices on what to do with the process (kill task, unlock, etc.) along with a list of file options such as delete or rename. On Unix and Unix-like systems, utilities such as the fstat and lockf utilities can be used to inspect the state of file locks by process, by filename, or both.
On Windows systems, if a file is locked, it's possible to schedule its moving or deletion to be performed on the next reboot. This approach is typically used by installers to replace locked system files. Using EMCO MoveOnBoot utility, it's possible to move, rename and delete locked files located on non-removable disks on the next Windows reboot.
Read more about this topic: File Locking