Originally Posted by
blackblade
This for emphasis.
I had a similar problem when upgrading to weakauras 2, I managed to fix it by deleting the addon and re-downloading it (your setting should be unaffected, as they're stored in your WTF folder). The core package had become corrupt or wasn't installed completely, and the dependancies were showing as 'dependancy disabled' with the core addon not appearing in WoW's addon list.
I can't remember if Auctioneer is a Wow-interface only thing or not, but if you're using curse client to manage addons, if it says 'Modified' in the addon list, do a force-update to get it back in sync.