You must have encountered this issue before – when you are trying to delete a file, Windows pops up a dialog telling you that Windows could not remove it, the file is used by an other application. As many of us know, we could use the famous freeware named UNLOCKER to unlock the file and then delete it. But maybe you don’t know that if your operating system is Windows 7, you could delete the obstinate file without any third party software, the method is deadly simple.
Press the Windows key and R to bring out the run dialog, then type perfmon.exe /res to bring out the built in Windows Resource Monitor( or you can launch Resource Monitor via the start menu search ).
Now navigate to the CPU tab, you will see a edit box named Search Handles at the right side of Associated Handles label, click to active it then type the filename which you want to unlock then press enter, you will see all the processes which is occupying the file you want to remove. Right click on them and choose End Process from the pop up menu.
Now your file is free, it’s not the slave of any process anymore, you could move it to Recycle Bin or delete it permanently.