Need help with a broken ForEach

I am attempting to write a script that takes a list of IP address’s, finds alive hosts, then checks to make sure that a specific service is installed. If the service is NOT installed it should be adding the IP address to the $notinstalled array. This is not working as I thought it should.

Could someone tell me what I am doing wrong in that specific ForEach section? This script is a learning / work in progress as I have never written a powershell script before.

I have attached the entire script, such as it is.


ForEach ($entry in $alivehosts){
	$svc = Get-Service -Display $sname -ComputerName $entry -ErrorAction SilentlyContinue
	IF( -not $sname) {$notinstalled += $entry}
	else { $sname + " is installed on " + $entry}

You’re checking $sname. I don’t see you defining it anywhere.

If the service doesn’t exist, $svc would be null. $sname presumably contains the name of the service you’re looking for. It’ll never be empty.

if (-not $sname) is never going to be True; $sname is a string you’ve defined. I assume you meant to do if (-not $svc) in that conditional.

Pounds head on desk

Can’t believe I did that. ($sname VS $svc)

Is it kosher to ask why the try-catch-finally is only catching and logging one error? Do I have to do a ForEach for each error?


Well, you’ve suppressed the error by using -EA SilentlyContinue. You have to use -EA Stop to trigger Try/Catch. See our free ebook on error handling - under the “Resources” menu on the site.

Your try/catch block should probably be inside the foreach loop, not the other way around (unless you want the whole loop to abort as soon as an error occurs.)