How to Find Out Which Windows Process is Using a File

Ever try to delete, move, or rename a file only to get a Windows system warning with something like one of these messages?

• "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"

One of the best ways to handle locked files or folders is to use the free Microsoft program Process Explorer. Here is how to use it to find out what program, DLL, or handle is using a file or folder. You will need to run as administrator.

How to find out what program is using a file

In Windows 7 or 8, the system message may tell you what program is using the file. If it doesn’t or if you are using Windows XP, there is a simple way to find the program:

1. Open Process Explorer, running as administrator.
2. On the toolbar, find the gunsight icon on the right (shown highlighted in the figure shown below).
3. Drag the icon and drop it on the open file or folder that is locked.
4. The executable that is using the file will be highlighted in the Process Explorer main display list.

How to find out which handle or DLL is using a file

1. Open Process Explorer, running as administrator.
2. Enter the keyboard shortcut Ctrl+F. Altenatively, click the “Find” menu and select “Find a Handle or DLL”.
3. A search dialog box will open.
4. Type in the name of the locked file or other file of interest. Partial names are usually sufficient.
5. Click the button “Search”,
6. A list will be generated. There may be a number of entries.
7. An individual handle in the list can be killed by selecting it and pressing the delete key. However, care is necessary when deleting handles, as instabilities may occur. Often, just rebooting will free a locked file.