Find out which process is locking a file

From time to time there is an issue caused by a conflict while accessing a file. For example the update to a newer version of YSoft SafeQ may fail if a third party application is locking some of the YSoft SafeQ files. This article describes how to find out which application is holding a handle to a file. Once the application is identified, it is best to terminate it before attempting to make an update again. The common cause of such a conflict is a backup software or a security application.

Imagine the update is failing as the exclusive lock to files in C:\SafeQ6\FSP\Service\Spooler 6.0.49.1 directory cannot be obtained. Two approaches described below are among the most effective ones.

Task Manager

1. Run Task Manager (e.g. Windows + R → type in taskmgr → press Enter)

2. Go to tab Performance → click Open Resource Monitor

   

3. In the Resource Monitor switch to tab CPU → find the section Associated Handles and type in the name of file or folder you are interested in

   • by typing in spooler you will find any handles for files that are stored in a directory having this name

     

If you cannot find what locks your files, it is best to double-check the situation with a Process Explorer. Process Explorer seems to provide a bit more information in some situations.

Process Explorer

1. Download application at https://docs.microsoft.com/en-us/sysinternals/downloads/process-explorer

2. Run the application

3. In the upper menu choose Find → Find Handle or DLL...

4. Type in the name of file or folder you are interested in and press Search

   • by typing in spooler you will find any handles for files that are stored in a directory having this name