I've just upgraded to v3.7.3 today and as usual after upgrading I'll check to make sure all are fine and working as usual. The strange thing is, out of the 3 categories, 2 appears to have problem and return "Not Found" while the 3rd category works just fine.

I'm not a tech guy so hopefully I'm not alone with this problem. I've search the forum and found nothing close to what I'm experiencing now.

Any help is very much appreciated.

Hat is the URL?
Are there any posts assigned to that. Category?

Hi juggledad thanks for your reply.

Here're the urls
wellnessreviews(dot)net/hair-loss/
wellnessreviews(dot)net/hives-rash/

Yes there are posts in there. It was working all this while until I upgraded to v3.7.3

I don't think this is a theme issue at all. Here are couple things to try
1) swap to twenty-eleven and see if it works or not
2) change the permalinks to default and then back to what you have and see if it works
3) disable all plugins and see if it works
you didn't by any chance upgrade WP?

Thanks juggledad. I'll try your suggestions. I'm still at WP 3.2.1.

This WP plugin "Q2W3 Post Order" is the culprit.