Wow, 3.0....that's back from like '99 or 2000
No reindex in the control panel as it's something that is no longer needed.
404 sounds like it can't find the page, possibly a link to an old script. Can you get them to post the full url that they are being sent to when they get that error.
As for the missing links. Are those links that were made within posts or from somewhere else?
