g1smd - 8:35 pm on Oct 24, 2006 (gmt 0)

Get a meta robots noindex tag on ALL of the pages that would present an "Error. You are not logged in" message to bots. That includes any stuff like newthread.php, newreply.php, sendpm.php, login.php, and just about anything else that is not a thread or is not an index of threads.

Alternatively use robots.txt to exclude those URLs, but it is far better to do by using the meta tag.

Each thread has at least 10 URLs that can access it. Work on getting only ONE URL version indexed for all threads.

In particular, pay attention to the "previous" and "next" links and get those fixed. There are two alternative ways to do this. One is to modify those links so that they go through a 301 redirect that points to the correct thread number. That bit requires some extra scripting. The other is to calculate the correct thread number and include that in the link, instead of appending the &goto= parameter to the existing thread number, which creates duplicate content.