MyBB Community Forums

Where is that on the forum? LOL I am just curious because this bot has been a headache long before I started using mybb. That is what it is viewing .. and come to think of it so does google LOL

It happens when you try to do something you do not have permissions for.
For example post in a forum that members are not allowed to post or try to view a forum that has been set to not be viewable by the usergroup you are in.
In your case, I guess your guest permissions do not allow the bots to do something they are trying (probably view some forums)

http://community.mybboard.net/modcp.php

That's the error they're seeing