Go into Options->Permalinks and check the setting for Category base:. It should be blank since you’re using the default /category/[category_name]/ format.
I “solved” this the same night, but I got an error when I tried to reply :\
In response to Hella, Options -> Permalinks was already set to blank for Category Base. So here’s what I did do to “solve” my problem:
I had to change Category Base to anything but the default — in my case I chose “topics”. Now all permalinks work fine. To “fix” my example from above (http://www.aurallove.com/category/music/ is broken), the working URI is http://www.aurallove.com/topics/music/. Weird problem though. I wanted to post this in case anyone else has run into the same issue.
I had the same problem with version 2.5 (the links to the Categories did not work on the actual site). After reading your experience, I realizedthat this could be problem with the .htaccess file. In my case, the .htaccess file had the wrong permissions (it was not writable) so WordPress could not update it. It did however place the code it would have written to .htaccess in a text area at the bottom of my Permalink Settings page. I simply updated my .htaccess page manually by copying and pasting this code and changed the permissions to 777 so that WordPress will not have similar problems in the future.
The problem began for me when I changed the Permalink settings to “Day and Name.” This change would have been written to the .htaccess file but the file was not writable. So when WordPress went looking for my permalinks (Categories), I got a “page not found” error in my browser because it was looking for the links with a different URL. Now it’s working fine.
I think in your case, when you chose “topics” as your Category Base, WordPress rewrote the instructions to .htaccess so that links were working again. This is just an educated guess, as I’m very new to WordPress.
You might double check your .htaccess file using an FTP program (you may have to “show invisible items”). Just be sure that your .htaccess file has read and write permissions (I don’t know if you need execute–I don’t think so).
Hope this helps. Your post certainly helped me.
Thanks,
Todd
