I recently came across an odd problem the customer got on his SharePoint server: when the clients had the Office Live add-on installed they were constantly refused with a 403 error. The problem is well described here.
If you have this problem, there is a fix for you: 970946.
If you do not want to install the fix, you might consider to filter the UserAgent string you receive on the server (well, you should filter it before the web request is processed on the server) as one of my customers is testing: if the UserAgent string contains the word “Mozilla” and “Office”* or “non-browser” or “FrontPage”*, just remove the unwanted token.
Carlo
Quote of the day:
All things are difficult before they are easy. – Thomas Fuller