Exploring the Get-PSSnapin Cmdlet in PowerShell

Welcome back to Wahmans PowerShell blog! Today, we’re diving into the Get-PSSnapin cmdlet, a versatile tool for managing PowerShell snap-ins. According to Microsoft, this cmdlet “gets the Windows PowerShell snap-ins on the computer.” But what does that really mean in practice? Let’s break it down and look at how we can use it effectively.

What is a Snap-in?

PowerShell snap-ins (PSSnapins) are legacy modules used to add cmdlets and providers into the environment. They were more common before the introduction of modules in PowerShell 2.0 but are still occasionally used in certain enterprise scenarios or with older products that haven’t transitioned to modern modules.

Basic Syntax

Get-PSSnapin [-Name <String[]>] [-Registered] [CommonParameters]

Let’s Explore 4 Use Cases from Beginner to Advanced

1. List All Currently Added Snap-ins (Beginner)

This will show all snap-ins that are currently loaded into your PowerShell session:

Get-PSSnapin

Output: A list object showing name, version, and description of each loaded snap-in.

2. Show All Registered Snap-ins on the System (Beginner)

If you want to see all snap-ins available on your system (not just the ones currently added):

Get-PSSnapin -Registered

This can reveal additional functionality available to your environment that isn’t loaded by default.

3. Check If a Specific Snap-in Is Installed (Intermediate)

If you’re writing a script and want to validate that a certain snap-in is registered:

if (Get-PSSnapin -Registered | Where-Object { $_.Name -eq "My.Custom.Snapin" }) {
    Write-Output "Snap-in is registered."
} else {
    Write-Output "Snap-in is not registered."
}

This snippet is handy for pre-deployment validation of pre-requisites.

4. Dynamically Load a Snap-in If Not Present (Advanced)

Combining Get-PSSnapin with Add-PSSnapin allows for dynamic environment setup. This is useful in complex automation tasks:

$snapinName = "My.Custom.Snapin"

if (-not (Get-PSSnapin | Where-Object { $_.Name -eq $snapinName })) {
    if (Get-PSSnapin -Registered | Where-Object { $_.Name -eq $snapinName }) {
        Add-PSSnapin $snapinName
        Write-Output "$snapinName added successfully."
    } else {
        Write-Warning "$snapinName is not installed on this system."
    }
} else {
    Write-Output "$snapinName is already loaded."
}

This is a great way to make scripts more portable and user-friendly.

Final Thoughts

While modules are the preferred way to extend PowerShell these days, understanding and using snap-ins can still be valuable when dealing with legacy systems or third-party tools that haven’t been modernized yet. Get-PSSnapin offers essential insights into the components available in your current session or installed on the system.

Happy scripting, and I will see you in the next post!

Wahmans Powershell Blog

Get-PSSnapin