LockHunter

LockHunter is a great tool for deleting files blocked by something you do not know, it's one of the most popular file unlockers. It has great features and very powerful. With this small utility, you can find what process blocked your file, with detail information of the process, and then you can decide to kill the process. for finding the processes which blocked files or folders, the LockHunter performs much better than other alternatives,it's more powerful.

LockHunter integrates into Explorer menu,it's more convenient and easy to use.

Also, LockHunter deletes files into the recycle bin, so you may restore them if deleted by mistake.So it's safer.

Highly recommend this small utility.

Pros:
free and Powerful