Create self-signed certificat e script.ps1 is not digitally signed

I'm attempting to create a self signed certificate according to the steps suggested to enable the AppInsight for IIS monitoring. Can someone help me get around this error excecuting the script provided by SW?

File C:\temp\Create self-signed certificate script.ps1 cannot be loaded. The file C:\temp\Create self-signed certificate script.ps1 is not digitally signed. The script will not execute on the system. Please see "get-help about_signing" for more details..

At line:1 char:2

+ & <<<<  '.\Create self-signed certificate script.ps1' xxx.xxx.xxx.xxx 3650

    + CategoryInfo          : NotSpecified: (:) [], PSSecurityException

    + FullyQualifiedErrorId : RuntimeException