MyBB Community Forums

Is there any plugin which avoids members to start new thread in specific forums before the post count, admin has specified?

You can use the Promotion System for this. AJS wrote a very nice tutorial on how to use it:

http://community.mybb.com/thread-92069.html

Yeah.. I know about the promotion but that'd become very lengthy, for example, editing the permissions of all forums and other works too...

I just think it's pretty useless when you can do that directly in MyBB. But try one of these plugins then:

http://www.mybbcentral.com/thread-2601.html
http://mybbsource.com/mods.php?act=view&id=50

You'll need to change the compatibility line in either one of them.