301 redirects disabled, vBSEO still redirects to new archive

This is a feature enabled inside vBulletin. Go to vBulletin Options and then access the Search Engine Friendly Archive area. And edit the appropiate options from their to link to the actual thread instead.

Hmmm, do you have any modifications installed in the Archive?
Also do you think you could link us to your forums?

Hello PageUp,

Originally Posted by PageUp

I have Archive Options: set to Rewrite vB's Archive. Isn't that supposed to mean that the old archive threads will NOT be redirected to the new archive (if you change the rewrite archive root)?

'Rewrite vB's Archive' means the URLs in these pages will be rewritten to the actual threads. Thus, yes, they will physically point to your core threads. However, they are not 301 redirected meaning that if someone gets to the original archive thread via previous links, bookmarks, etc., they won't be redirected to the core thread. I suggest having both, Rewrite + 301 Redirect Archive Pages option activated.

In my case, old threads like forum/archive/index.php/t-333.html are redirected to forum/sitemap/t-333.html. How can I disable those redirects?

They are redirected because you have selected to have your archives in '/sitemap/' now. You can, however have your sitemap reside in it's original location '/archive/index.php/'. The redirect is used to prevent duplicate content issues and let spiders (and users) know where to find it.

My fear is that Google will consider this duplicate content, although of course the archive threads are not directly linked from within the website.

As long as the previous content is 301 redirected, it shouldn't be considered duplicate content. 301 redirects are google "safe" way of moving content (see http://www.google.com/intl/en/webmasters/3.html)

I hope this helps =)