How to Use Resource Monitor to Find Which Process Has Locked a File?

I know many folks that use Windows SysInternals Process Explorer to gather information about running processes and their open handles. There is an excellent but less familiar utility in-built with Windows 7 and higher, called Resource Monitor which provides complete details of running processes, their associated handles and associated modules (for example, DLL files).

1. To launch Resource Monitor, press WinKey + R, type resmon.exe and press ENTER.

2. Select the CPU tab, and expand Associated Handles by clicking on its title bar

3. Type a file name or part of the file name in the text box provided. This should list the processes which are currently accessing the file(s)

Bonus Tip! You can also type a registry key in the search field, which would cause Resource Monitor to show the registry handles with the corresponding process names.

View Associated Modules for a Process

There is another option wherein you can view the list of modules that are in use by a given process. Simply select one or more processes in the Processes section, and then expand the Associated Modules section to view the list of modules used by the selected processes.

Resource Monitor proves to be an useful tool to investigate processes and locked files, and can come in handy especially when you forget to bring your troubleshooting toolkit along when fixing a friend’s PC. « Associated Handles » and « Associated Modules » is a nice feature addition in Windows 7 and higher. You can also use Process Explorer to find this info. Check out Know which process has locked a file.

Incidentally, you may’ve also noticed that the « File in Use » dialog in Windows 7 and higher, displays the Process Name as well.