If you have tried to run a PowerShell script that isn’t signed, you’ve likely run into the security error “File … cannot be loaded.  The file is not digitally signed.  The script will not be executed on the system. “  This means that the script is not trusted to be run on your system.

If you’d like to sign the script, here is a walkthrough:

http://blogs.technet.com/b/heyscriptingguy/archive/2010/06/17/hey-scripting-guy-how-can-i-sign-windows-powershell-scripts-with-an-enterprise-windows-pki-part-2-of-2.aspx

Alternatively, you can change your signing policy.  This tends to be the practice most of the time… 😉

http://technet.microsoft.com/en-us/library/ee176961.aspx

You can choose, “Set-ExecutionPolicy Unrestricted” or, replace unrestricted with “Restricted”, “AllSigned”, or “RemoteSigned”