BlockBreakEvent not cancelling?

I have several instances of my code where I need to disable block breaking, however when I use event.setCancelled(true);, players are still able to break the blocks regardless. Could there be something overriding this even though I have the priority set to high?

 

All I know is that it works for me

 

According to this (http://forums.bukkit.org/threads/getting-your-priorities-straight-the-plugin-version.788/), highest priority, is actually close to the lowest, try setting to lowest, and see what happens.

 

Highest means it is ran last, which means it's code is ran over the others. Low priority means it is ran first, and thus can be overridden by other code.

I tested this extensively by removing all other plugins, and even removing lines of code not essential to the system, and yet the event is still not cancelled. I'm honestly at a loss for what to do.

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