Which DLL are used by a process ?

MS-DOS_iconSometimes, you need to move or update a DLL file, but you receive an error message saying : « Access denied ».
It’s not always a file access right problem.
Mayby this library is currently used by a process. To found out which one, just type use the tasklist command in a DOS / Powershell prompt :

tasklist /m your_dll_file.dll

Simple !

Furthermore, if you want to know which regular file (not DLL) is being used by a program, you can download and run process explorer from Windows Sysinternals website. Then « Find > Find Handle or DLL ».