heroku : File C:\Users\marc\AppData\Roaming\npm\heroku.ps1 cannot be loaded because running scripts is disabled on this system code example

Example: The file \AppData\Roaming\npm\yarn.ps1 is not digitally signed.

Remove yarn.ps1 from the directory C:\Users\%username%\AppData\Roaming\npm\ then try clearing the npm cache at C:\Users\%username%\AppData\Roaming\npm-cache\