The Add-PSSnapin command should execute in less than a second. But, if your machine has restricted access to the Internet, it could take 60 to 90 seconds to execute. This delay occurs when PowerShell is verifying the digital signatures on the snap-in that is being loaded. To verify the signatures, PowerShell needs to download the certificate revocation list and, if Internet access is restricted, it can take 60 to 90 seconds for this attempt to time out.
You can disable the check for the certificate revocation list by doing:
- Open "Internet Options" in the Control Panel or Internet Explorer
- Click the "Advanced" tab
- Scroll down to "Security"
- UNcheck "Check for publisher's certificate revocation"
- UNcheck "Check for server certificate revocation"
- Click OK