I went through each of those steps, off and online, reboot each time, started game offline, started game online...
No change.
I think there is an old file somewhere trying to locate a server no longer valid when I am offline causing the issue.
Short of TMarc's suggestion of doing a full reinstall of the game, I think I'm just gonna shelf this for now.
Unless someone knows what line in which file is looking for the possibly extinct sever, I think I'm at a point with this that it's no longer worth the hassle.
Thanks for your help.
