How to Use Invoke-Command in PowerShell: Syntax and Examples

Use Invoke-Command in PowerShell to run commands locally or on remote computers by specifying the -ScriptBlock and optionally the -ComputerName. It lets you execute scripts or commands on one or many machines easily and securely.

Syntax

The basic syntax of Invoke-Command includes specifying the command or script block to run and optionally the target computer(s).

• -ScriptBlock: The commands or script to run.
• -ComputerName: The remote computer(s) where the command runs.
• -Credential: Optional user credentials for remote access.
• -Session: Use an existing session for repeated commands.
• -ArgumentList: Passes arguments to the script block.

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Invoke-Command -ScriptBlock { <commands> } [-ComputerName <string[]>] [-Credential <PSCredential>] [-Session <PSSession>] [-ArgumentList <Object[]>]

Example

This example runs a simple command locally and then remotely on a computer named 'Server01'. It shows how to get the current date and time.

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Invoke-Command -ScriptBlock { Get-Date }

Invoke-Command -ComputerName Server01 -ScriptBlock { Get-Date }

Output

Monday, June 10, 2024 10:15:30 AM
Monday, June 10, 2024 10:15:32 AM

Common Pitfalls

Common mistakes include:

• Not enabling PowerShell remoting on the remote machine (Enable-PSRemoting must be run).
• Using incorrect credentials or missing -Credential when required.
• Trying to run commands on remote computers without network access or firewall exceptions.
• Forgetting that Invoke-Command runs in a different session, so variables from your local session are not available remotely.

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## Wrong: Trying to use local variables remotely without passing them
$localVar = "Hello"
Invoke-Command -ComputerName Server01 -ScriptBlock { Write-Output $localVar }

## Right: Pass local variables using the -ArgumentList parameter
$localVar = "Hello"
Invoke-Command -ComputerName Server01 -ScriptBlock { param($msg) Write-Output $msg } -ArgumentList $localVar

Output

## Wrong: No output or error about variable not found

## Right: Hello

Quick Reference

Parameter	Description
-ScriptBlock	Defines the commands or script to run.
-ComputerName	Specifies remote computer(s) to run the command on.
-Credential	Provides user credentials for remote access.
-Session	Uses an existing PowerShell session for commands.
-ArgumentList	Passes arguments to the script block.

Key Takeaways

Invoke-Command runs commands locally or remotely using a script block.

Always enable PowerShell remoting on remote machines before use.

Use -Credential to provide credentials when accessing remote computers.

Pass local variables to remote sessions with -ArgumentList and param().

Check network and firewall settings to allow remote command execution.