Have you tried unlocker?
http://www.filehippo.com/download_unlocker/
Steps to Removing a Locked or Undeletable File
1.
Download and install Unlocker . Accept the defaults when installing.
2.
Open up Windows Explorer and navigate to the file you wish deleted.
3.
Right click on the file, and select "Unlocker". A window will appear giving you a list of processes (running programs) that are holding open the file. Scrutinize the list to make sure you really don't want these processes to continue to hold open the file.
4.
If Unlocker cannot find any process locking the file, preventing it from being deleted, it will tell you that, and you can either delete it manually, or ask the program to delete it for you.
5.
If you are satisfied that you still really want to remove the file, you have a few options. You can select "Delete" in the drop down box (it defaults to "No action") to let unlocker do it for you, or you can select "Unlock all" to cause Unlocker to force all the processes using the file to unlock it. In such a case, you will now be able to delete it manually using Windows Explorer (unless the process immediately reestablishes a lock before you can do anything). Alternatively, you can select the process locking the file in the dialog box window and click the "Kill Process" button. This will terminate the process that is currently holding the file open (that is, "kill" it). You can then manually delete the file from Windows Explorer.
6.
If you have changed your mind, and have decided not to delete the file after all, simply hit the "Quit" button without doing anything (or hit the ESC key) and Unlocker will exit without harming your file.