PowerShell script to check an application that's locking a file?

You can do this with the SysInternals tool handle.exe. Try something like this:

PS> $handleOut = handle
PS> foreach ($line in $handleOut) { 
        if ($line -match '\S+\spid:') {
            $exe = $line
        } 
        elseif ($line -match 'C:\\Windows\\Fonts\\segoeui\.ttf')  { 
            "$exe - $line"
        }
     }
MSASCui.exe pid: 5608 ACME\hillr -   568: File  (---)   C:\Windows\Fonts\segoeui.ttf
...

You should be able to use the openfiles command from either the regular command line or from PowerShell.

The openfiles built-in tool can be used for file shares or for local files. For local files, you must turn on the tool and restart the machine (again, just for first time use). I believe the command to turn this feature on is:

openfiles /local on

For example (works on Windows Vista x64):

openfiles /query | find "chrome.exe"

That successfully returns file handles associated with Chrome. You can also pass in a file name to see the process currently accessing that file.

I was looking for a solution to this as well and hit some hiccups.

1. Didn't want to use an external app
2. Open Files requires the local ON attribute which meant systems had to be configured to use it before execution.

After extensive searching I found.

https://github.com/pldmgg/misc-powershell/blob/master/MyFunctions/PowerShellCore_Compatible/Get-FileLockProcess.ps1

Thanks to Paul DiMaggio

This seems to be pure powershell and .net / C#

Posted a PowerShell module in PsGallery to discover & kill processes that have open handles to a file or folder. It exposes functions to: 1) find the locking process, and 2) kill the locking process. The module automatically downloads handle.exe on first usage.

Find-LockingProcess()
Retrieves process information that has a file handle open to the specified path.
Example: Find-LockingProcess -Path $Env:LOCALAPPDATA
Example: Find-LockingProcess -Path $Env:LOCALAPPDATA | Get-Process

Stop-LockingProcess()
Kills all processes that have a file handle open to the specified path.
Example: Stop-LockingProcess -Path $Home\Documents

PsGallery Link: https://www.powershellgallery.com/packages/LockingProcessKiller To install run:
Install-Module -Name LockingProcessKiller

You can find for your path on handle.exe.

I've used PowerShell but you can do with another command line tool.

With administrative privileges:

handle.exe -a | Select-String "<INSERT_PATH_PART>" -context 0,100

Down the lines and search for "Thread: ...", you should see there the name of the process using your path.