Welcome to my nightmare. There's a bug in the phone-home for activation, apparently added by last Sunday's update - TurboTax worked on my computer just fine before then.
I've spent hours on the phone with several different support people, none had any inkling about what's going on. Apparently they don't talk to each other or put notes in a file for the bug notice, since I had to start from scratch with all of them. They tried all sorts of things for my machine - like strip out all security protections, which should absolutely not be a prerequisite to use of any program - none of which worked a bit. Even shutting the proxy server leaving the thing totally naked didn't help at all.
Two items of note:
1) I also use Quicken. It continues to work just fine, even with the new version downloaded yesterday.
2) H&R Block also works just fine.
