Feed not generating

Hello all,

I recently updated a wordpress install that hadn’t been touched since June of 2010. I didn’t pay attention to what the version was prior to updating, but the first thing I did before beginning to use the blog again was to update to the current version.

I’ve got it all updated and can add posts and such, but WordPress doesn’t seem to be generating a feed:

http://tech.d181.org/blog/feed/ gives a 404 feed error. I’ve reverted to the default template and disabled all plugins but that hasn’t worked. The feed did work a year ago.

Thanks for any suggestions.
Eric