I'm having a rather serious issue with Role Manager on my weblog with concern to categories (I'm using the plugin available at http://www.im-web-gefunden.de/wordpress-plugins/role-manager/ ".
The issue is that when a user logs in, unless they have the ability to "Manage Categories" the php script in the main index won't get past the have_posts() loop, and it'll display the "Sorry, but you are looking for something that isn't here" text (also the categories that are supposed to be listed in the sidebar will say "No categories", though this might simply be connected to the loop not running as it should). I've fiddled around with it, and users with the ability to "Manage Categories" (such as administrators) will not get this error, nor will users that are not logged in. If anyone has any idea how this happened or what a possible fix would be, I would be very grateful. This issue seemed to have started when I installed the Role Manager plugin, but now that it's there even deactivating the plugin isn't helping. Unless I can get it figured out, it seems like I'll have to reinstall wordpress entirely.