I'm running 6.5.2 on a Mac OS X server with the default MySQL/PHP configuration that ships with the operating system (MySQL 4.1 and PHP 4.4.1). That said, here goes. I upgraded from ubb.classic yesterday because OS X only runs mod_perl, thus rendering ubb.classic unrunnable. I ran the import thread and everything worked just fine.
Today, however, whenever I am logged in and try to read threads, all of the links try to take me to a file called "show5.php" instead of "showflat.php." I have done several searches of the UBB code and have no idea where this "search5" business is coming from, and it's very frustrating. I can read threads just fine when I am not logged in, but I am unable to make posts because of this problem. Obviously this isn't a consistent issue, as two people have made posts since I have upgraded; however, there is usually much more activity than this so I can only assume that the problem is not limited to just myself.
Any help that can be offered, and offered quickly, would be fantastic.