Zoom has stopped working.

Woke this moring to big Zoom problems. 

Zoom Workplace app refuses to open in any way. I've tried restarting my computer multiple times but no luck. I tried reinstalling the app, but it refuses to do that too. I can't open any of my meetings at all, and when I try to redownload the app it says "the application I'm trying to install is not approved by Microsoft". 

All this is just totally unacceptable, there is zero reason for any of this. Everything else on my computer is working perfectly fine, except Zoom. This is costing me money!