I am having the same problem with RSS Feed as patricer who had said:
I'm trying to create a feed with FeedBurner (using the FeedBurner Feed Replacement plug-in) and it doesn't seem to recognize the feed I enter (http://MYDOMAIN.com/blog/?feed=rss2). I checked to see if another feed reader would recognize it and it doesn't.
Now for me, when I go to my blog's sidebar Meta widget and click on "Comments RSS" it works fine. When I try "Entries RSS" or when I click on the RSS icon in the browser address bar, I get this page that says:
HTTP Status 400-You must provide a feed uri
type Status report
message You must provide a feed uri
description The request sent by the client was syntactically incorrect (You must provide a feed uri).
I have the FeedSmith plugin, I have the proper FeedBurner url (it works with other things). But those two links (the "Entries RSS" and the RSS icon in the browser address bar) do not work.
I recently changed my own .htaccess file so I could have my post-name in my permalinks. I do not know if this is related.
I am using the recent WP version. My blog is http://www.newyorktraveler.net
Things I have tried so far and haven't worked:
entering in a different feed url ( http://newyorktraveler.net/?feed=rss2 and http://feeds.feedburner.com/NewYorkTravelernet?format=xml)
deactivating my Slashdiggalicious plugin
changing permalinks to show category/postname instead of just postname
Nothing has worked yet. I'd sure like help with this. Thanks!