.ps1 cannot be loaded because running scripts is disabled on this system. For more information, see about_Execution_Policies

If you ever worked with NuGet in VisualStudio and faced the error above in the Packet Manager Console – you might need to set the Execution Policy accordingly.

http://technet.microsoft.com/en-us/library/hh847748.aspx

Example

Set-ExecutionPolicy Unrestricted -scope LocalMachine

BUT since both versions of PowerShell (x86 / x64) will use their own Execution Policy you need to set them in both versions too!