Script not doing anything when ran as a service

PowerShell Tools
1 
Tool: Visual Studio Code
Version: 	2022.3.0

Hi all,

I’ve written a script which does some application metering. The basic premise is… Script reaches out to Powershell Universal, gets a list of applications to meter. It then creates some event subscriptions to find when the application is launched. It then hits a different API on my Powershell Universal server to upload the data. If I run it in a normal Powershell window, it works fine. When I package it as a service, it doesn’t work.

Below is the code.

(<# This function is called when the service is started. Once this function re - Pastebin.com)

I put in 3 start-transcripts within it, which all work when ran manually, but when done as a service it just returns that the transcript has started and nothing else. Additionally, the data doesn’t hit the server.

2

Are you compiling for Windows PowerShell or PS7?

3

Compiling for Windows Powershell

4

Ok. Thanks. I will take a look.

5

Hi Adam, just wanted to see if you had any luck one way or another with this.

6

Hey @Jori - Sorry for not circling back sooner. I tried creating a service and am not seeing issues with it running the script but I do wonder if it’s possible your script may be encountering errors while running.

One thing that might be a good idea would be to put a try catch around everything to rule out a terminating error throwing and causing the rest of the script to fail.

You should do somthing like:

function OnStart() { 
    try {
        RunScript()
   } catch {
       # Write exception to log file
   }
}

function RunScript() {
  # Your script here
}
7

Hi Adam,

I’ll give that a try. I haven’t had a problem with the service running… It runs fine, it just doesn’t detect when an application is launched when it’s running as a service. Running it just in a PowerShell window it does. I’ll try wrapping it with try catch though.

8

Hmm ok. I wonder if it’s some sort of permission thing. You’re running the service as local service?

9

Just tested that quick. It’s running as System, so I opened up a powershell window as SYSTEM using psexec. When ran as system (and not a service) it still works, so not a permission thing.

At this point my only thought is the service doesn’t like the WMIEvent subscription and FileWatcher for some reason…