I run into this all the time. I install PowerShell, go to run a .ps1 script and it yells at me saying that the script
is not digitally signed. The script will not execute on the system. Please see "get-help about_signing" for more details…
To fix it you'll need to execute this command:
(And in Windows 7 you'll need to have Administrator rights in the console windows as well because it edits a registry key)
Technically, you're introducing a security vulnerability, but there's no way I'm going to sign every little script that I write. That's just asking too much!