guests are allowed to reply?

Edit: I tried another search and found the answer, it's because of the converter.
Feel free to delete this if you want, mods.

hi,
on my forum I just realised that guests are allowed to posts even if I have changed the settings in both all the forums and in guest-settings to "no".
Any ideas??
This is a huge problem as I have some annoying people that spam the forum.

After doing some testing I see that the guests are treated just the same as members. When I change settings for members to read only, then neither members or guests can post/reply.
But when I set it so that members can post/reply, so can guests.

I need help