Okay, the problem is that sometimes we get linked or redirected to
http://www.lcficmbs.com/ubb/ubbthreads.php/ubb/cfrm and sometimes it's
http://www.lcficmbs.com/ubb/ubbthreads.php?ubb=... Since the some of the cookies are created for the "/ubb/ubbthreads.php/" path, the login fails for the shorter URL. This is definitely a config-issue or a bug in the UBB software and there's nothing we user can do to solve this.
Oh, and sometimes it helps to switch browsers.

Right now, I'm using Internet Explorer because Firefox wouldn't keep me away from the subdirectories.

Michael