Why isn't handles.exe discovering my DLL while ProcessExplorer can? - vb.net

Question

The problem:
On a windows server 2012 r2 box, I'm trying to use Chef to programmatically replace a .dll command component (aka a vb 6 library that I've registered on the box using regsvr32.exe) but when I try to copy over the file, the app pool of the website has a lock on it. I'm not sure if it matters, but the w3wp process is set to run as 32 bit via IIS.
My Solution (which isn't working):
In order to fix it, I was thinking about using a command line tool to find the reference to the dll and then recycling the app pool that's using it. Unfortunately, while I can get SysInternals' process explorer to find the dll, Handles.exe (the supposed command line version of process explorer) does not return anything. I was hoping that someone might be able to tell me how I was using handles incorrectly, or if there was a better tool for this.
Process Explorer - it has found my dll ComHelper.dll
Handles via command line - it has not found my dll ComHelper.dll
-- Edit --
This is the output of handles when I point it at w3wp while running as Admin

Answer 1

I would suspect you are running into access issues. Are you running Handle from an elevated command prompt ? Are you able to get any output covering handles in w3wp.exe (by using the pid of the process in handle.exe command line) ?
Looking at the handle enum output of w3wp.exe it seems,
listdll.exe -d ComHelper.dll
may be what you are looking for. Handle seems to be focused on files opened not dlls loaded. listdll is a tool that can be downloaded from sysinternals.

Answer 2

Alright so 32 bitness did matter. I ended up having to resort to powershell as opposed to trying to use handles. The code for finding a PID that has a lock on your file is scattered around the internet, but here's the link:
http://blogs.technet.com/b/heyscriptingguy/archive/2013/12/01/weekend-scripter-determine-process-that-locks-a-file.aspx (it's marv the robot's answer at the bottom)
For the record, this is what was suggested
$lockedFile="C:\Windows\System32\acproxy.dll"
$isLocked = $false
Get-Process | foreach{
$processVar = $_;$_.Modules | foreach{
if($_.FileName -eq $lockedFile){
$isLocked = $true
$processVar.Name + " PID:" + $processVar.id
}
}
}
This is what I had translated it into with my powershell noobishness
$lockedFile = "E:\Components\___ComHelper.dll"
$list = Get-Process
foreach ($process in $list)
{
foreach ($module in $process.Modules)
{
if ($module.FileName -ne $lockedFile) { continue }
$process.Name + " PID:" + $process.Id
}
}