I've been having a problem with broken links. When a user goes to click on a forum in a category, it shows an error that says "This link appears to be broken." This happened to every user who has tried accessing a post, on different web browsers. I've reinstalled the forum a number of times, deleted and remade databases, and the problem still exists.
Rename your .htaccess to htaccess.txt and see if the problem is solved.
Other way round, it needs to be called .htaccess to work...
Problem solved! When I downloaded MyBB, the file that SHOULD be called .htaccess was named htaccess.txt. , not sure why, but I renamed it and it's all fixed!
It's not called that by default as not every server supports it. You're supposed to rename it if you want to sue these URLs.