I've upgraded from vB 3.8.4 to vB 4.0.1 and followed the instructions part way through the upgrade process for adding indexes to the post and thread tables via the command line.
The search engine on my forum now only searches posts/threads/whatever made since the upgrade.
There were two messages on the admincp front page about rebuilding such and such with an 'Address' button next to each. I fired them both off, but they both timed out and I don't know what they were in order to repeat them. I don't know if this has any bearing on the search issue or not.
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