I just want to start a thread here on an issue that happened several weeks ago where our users are being prompted for authentication credentials with a pop-up, when things have been fine for over two years for us. I've opened a case, #01783640, and they are working on this issue. If you have a similar issue, open a case and be vocal about them working on a solution. So far they have not identified the issue.
The case has been escalated to the back line without word as to whats causing this. I heard that it could be part of the server farm upgrade they are doing, I've also heard it could have been a Microsoft update from several weeks ago. Regardless, they need to help us!