COM exception occurs only when I'm logged in to company domain

I have been working on a c# project in VS2017 Community. It's been fine for 6-8 weeks. I went away for the weekend and came back and I'm now getting an exception in my code that was not there previously.

System.Runtime.InteropServices.COMException: 'Catastrophic failure (Exception from HRESULT: 0x8000FFFF (E_UNEXPECTED))'

At work I am logged into our company domain with Admin privileges. I was also working on this at home on my laptop to I tried it there and it's fine. Copied the project from laptop back to my desktop in the office and again get the exception.

Finally tried logging out of the computer and logging back in as a local user, and the code runs fine, no exception.

When logging back into the domain I tried running VS2017 'as Administrator' but same problem - exception get thrown. I removed all the most recent Windows Updates but no relief.

I really have to be logged in to the domain in order to do most of my other work, so I'm fairly at a standstill right now.

The purpose of the offending code is very basic - just creating a playlist (from a folder full of files) The code here's the code I'm executing that throws the exception when I'm logged in as a Domain account:

WMPLib.IWMPPlaylist playlist = wmp.playlistCollection.newPlaylist("myplaylist");