Start Windows PowerShell with the "Run as Administrator" option. Only members of the Administrators group on the computer can change the execution policy.
Enable running unsigned scripts by entering:
set-executionpolicy remotesigned
This will allow running unsigned scripts that you write on your local computer and signed scripts from Internet.
Fonte: https://superuser.com/questions/106360/how-to-enable-execution-of-powershell-scripts
