How to Properly Put together a Function in Powershell - powershell

Question

I have done a ton of research on how to push this EXE to a remote PC using PSSession and all lines of code work when executed line by line. But i have had a hard time putting this into a function that makes sense and will execute all lines of code and successfully install the software with one push of a button. Not sure whats happening. It will install the exe locally when i tried to do put all lines of code in a function and run it. Can you please help instruct what i am doing wrong? Sorry i am a newbie at Powershell.
$dc1 = New-PSSession -ComputerName DC1
Copy-Item C:\TPAdmin\Greenshot-INSTALLER-1.2.10.6-RELEASE.exe -Destination C:\TPAdmin -ToSession $dc1
Enter-PSSession -Session $dc1
Invoke-Command -ScriptBlock {C:\TPAdmin\Greenshot-INSTALLER-1.2.10.6-RELEASE.exe /VERYSILENT /LOG="C:\SOFTWAREINSTALL.LOG"
Remove-Pssession $dc1

Answer 1

Enter-PSSession is for interactive use only, so not suitable for use in a function.[1]
Instead of using Enter-PSSession, pass the session you've created with New-Session to the Invoke-Command command's -Session parameter, which will run the command in the context of that (remote) session.
# Define your function...
function Invoke-InstallerRemotely {
param([string] $ComputerName)
$session = New-PSSession -ComputerName $ComputerName
Copy-Item C:\TPAdmin\Greenshot-INSTALLER-1.2.10.6-RELEASE.exe -Destination C:\TPAdmin -ToSession $session
# Do NOT use Enter-PSSession.
# Pass your session to Invoke-Command with -Session
Invoke-Command -Session $session -ScriptBlock {C:\TPAdmin\Greenshot-INSTALLER-1.2.10.6-RELEASE.exe /VERYSILENT /LOG="C:\SOFTWAREINSTALL.LOG"
Remove-PSSession $session
}
# ... then invoke it.
# Note that functions must be defined *before* they're called.
Invoke-InstallerRemotely -ComputerName DC1
[1] Using it in a function means that an interactive session on the target computer is entered, which you must exit interactively (by typing and submitting exit or Exit-PSSession) before the remaining statements in the function are executed, again locally.

Answer 2

As for …
Sorry i am a newbie at Powershell.
… that's all fine, as we all had to start from somewhere. However... a couple of things here:
Please be sure to format your posts, to encourage folks to want to
help. People frown on no doing that. Having to copy, paste and
reformat your post is well, extra unnecessary work. ;-}. We've al been there.
We have no idea how you are getting up to speed on PowerShell, but
use the freely available resources to limit/avoid all the
misconceptions, frustrations, errors, potential bad habits, etc.,
that you are going to encounter. Live on watching the videos on:
YouTube
Microsoft Virtual Academy
MSDN Channel9
Microsoft Learn
as well as the reference
and eBook resources.
Back to your use case. You do not say what is happening. So, you leave us to guess. Which is not really potentially helpful to you.
Nonetheless, you should just need to do this... in PowerShell v5x as it's require to use the -ToSession argument.
$DC1 = New-PSSession -ComputerName 'DC1'
Copy-Item -ToSession $DC1 -Path 'C:\TPAdmin\Greenshot-INSTALLER-1.2.10.6-RELEASE.exe' -Destination 'C:\TPAdmin'
Invoke-Command -Session $DC1 -ScriptBlock {C:\TPAdmin\Greenshot-INSTALLER-1.2.10.6-RELEASE.exe /VERYSILENT /LOG="C:\SOFTWAREINSTALL.LOG"}
Remove-PSSession -Session $DC1
I am not sure why you are doing that Enter-PSSsssion in the New-PSSession command as it is not needed. It's for standalone interactive sessions.
Explicit PSRemoting = Enter=PSSEssion
Implicit PSREmoting = New-PSSEssion
If all else fails for you on the copy via the session, then just use the normal UNC way to copy from source to destination.
Copy-Item -Path 'C:\temp\Results.csv' -Destination "\\$($DC1.Computername)\c$\temp"
See also:
Copy To or From a PowerShell Session