HELP! No one can place/destroy Blocks!

So Hi, im KekeMASTER and this is my first Thread or Post.
I had lately problems with my Bukkit Server. Like the title says nobody can place and destroy block anymore!
I am Admin and Owner of the Sever. And I've made an Permission but it won't activate. Please help me.
Should I post an Code here or something?
For all I have an Linux computer (Kubuntu) does this matter I think not.

 

if they're near the spawn, they wont be able to build, go to bukkit.yml and change the spawn-radius to 1
Hop i helped

 

Oh thanks I try It now.

This dosen't worked. More ideas?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Worldguarded?

 

I suggest using Bpermissions as your permission plugin.

 

What's with PermissionsEX?

OK it worked thanks for helping.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.