Hi,
the mpx is not an management pack, like Xin Guo already suggested.
but...There is an easier way to get this MP (which I am a fan of).
This MP is actuallly developed by SquaredUp and is available for download for free from their spin-off Cookdown. You can request the MP here:
Bye-bye VBScript. Hello PowerShell
https://www.cookdown.com/scom-essentials/powershell-authoring
Just fill out the short form and you will get the download link immediately per mail. Don't forget to check your spam/junk folder if you don't get the link right away.
Hope I could help you out!
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Stoyan Chalakov