I ran into an issue today that I had not seen before where clicking the RSS link from a Community Server blog presented an error message like this:
At first I thought there must be something wrong with the feed, but after a bit of troubleshooting and some time spent with Fiddler we found it was something else. The RSS page of the Community Server site was sending a 301 redirect to the FeedBurner feed link (like it is supposed to), but we were receiving another 301 redirect after that and then the above error.
It turns out that the FeedBurner setup was pointing to the http://sitename.com/username/rss.aspx page rather than the http://sitename.com/username/privaterss.aspx page. This was what was creating the loop. When using FeedBurner, the page that serves up the rss feed in Community Server sends a 301 redirect to the FeedBurner feed to let browsers know that your feed url has changed. However, FeedBurner was trying to pull the RSS feed from that same page and getting redirected back to itself, too.
When you setup your FeedBurner settings make sure you follow the instructions on the Syndication Settings page of your Community Server blog's control panel. It will direct you to use a feed that ends in the filename: privaterss.aspx. And if you run across this same issue in the future you will know where to look.