PowerShell "is not recognized as the name of a cmdlet": find out why it can't see the command

1. A script in this folder

This catches everyone once. You can see the file, and PowerShell says it doesn’t exist:

PS C:\scripts> deploy.ps1
deploy.ps1 : The term 'deploy.ps1' is not recognized ...

For safety, PowerShell doesn’t run things from the current folder unless you say so. It even suggests this at the end of the message. Add .\:

.\deploy.ps1

If that gives running scripts is disabled on this system, then this problem is solved, and the next one has started: see that article.

A path with spaces needs quotes, and also &, which means “run this”:

& "C:\Program Files\MyTool\tool.exe" --version

2. A program that isn’t in PATH

PATH is the list of folders searched for programs. You installed a tool, and its folder isn’t in the list. Find the file first:

Get-ChildItem -Path "C:\Program Files", "$env:LOCALAPPDATA" -Filter terraform.exe -Recurse -ErrorAction SilentlyContinue | Select-Object FullName

To try it in this window only:

$env:Path += ";C:\Tools\terraform"
terraform version

To keep it for your user:

[Environment]::SetEnvironmentVariable('Path', [Environment]::GetEnvironmentVariable('Path', 'User') + ';C:\Tools\terraform', 'User')

Use 'Machine' instead of 'User', from an administrator window, to apply it to all users.

Open a new window afterwards. A window that’s already open keeps its old PATH, and that’s why a tool you’ve just installed often isn’t found until you do. For a service or a scheduled task, you may have to restart it, or the machine.

Don’t use setx PATH "%PATH%;...", which you’ll see in old guides. It merges your user and system values into one, and cuts the result off at 1024 characters, which can break your PATH.

3. A module that isn’t there

Cmdlets come from modules. The name has a verb and a noun, such as Get-ADUser, and it isn’t found because that module isn’t installed:

Get-Module -ListAvailable ActiveDirectory
Get-Command Get-ADUser -All

Some come with a Windows feature, and others from the PowerShell Gallery:

# Active Directory, on Windows 10 and 11
Add-WindowsCapability -Online -Name Rsat.ActiveDirectory.DS-LDS.Tools~~~~0.0.1.0

# Active Directory, on Windows Server
Install-WindowsFeature RSAT-AD-PowerShell

# From the Gallery
Install-Module Az -Scope CurrentUser

Between versions: Windows PowerShell 5.1 and PowerShell 7 keep modules in different folders, so a module can work in one, and not in the other. See which one you’re in:

$PSVersionTable.PSVersion

Some old commands are gone from PowerShell 7 altogether, such as Get-WmiObject. Use Get-CimInstance instead.

4. A typo, or a Linux habit

Check the spelling with a wildcard, which also tells you what really exists:

Get-Command *firewall*

Commands from another system are common here:

5. It works by hand, and not in a task

Scheduled tasks and CI agents can run under another user, and they get that user’s PATH. In a script, use the full path. A command with a typo inside a script gives the error on that line, so read the line number in the message.