Hi, At the moment for my site, topics that are not found will return a HTTP/1.1. 200 OK status. I was thinking about using 404 errors, however, if viewtopic.php?t=101 was not found and gave a 404 error, would this prevent all of viewtopic.php from being indexed, or just viewtopic.php?t=101? Andrew.
Topics that are not found should either: 1) be 301 redirected to another page similar to the original topic or 2) return a 404 HTTP status code to indicate an error. You should NEVER return a 200 HTTP status for pages that do not exists. It's a terrible users experience. If you don't have a similar page you can 301 redirect the request to then setup a custom 404 page that has all your normal navigation (top navigation, left navigation, footer, etc.) with a clear message like "Oops! The page you requested doesn't exist." Include links to important pages or sections of the site... like a mini HTML sitemap so they will hopefully stay on the site and browse around looking for something similar. All search engines view each unique URLs as separate web pages. Soooo.... viewtopic.php?t=101 (doesn't exist) viewtopic.php?t=102 (exists) viewtopic.php?t=103 (exists) viewtopic.php?t=104 (exists) viewtopic.php?t=105 (exists) are all different pages in their index. If viewtopic.php?t=101 returns a 404 errors, the other URLs continue to remain indexed because they continue to return 200 Ok status to indicate they exist.