Every time I stop my server i get error as in http://paste.ubuntu.com/15580867/
Everything else is working fine i just don't know why is it happening and does it mean something to me.

I am having the same issue with Multiverse-Inventories v2.5-b408
http://pastebin.com/3RhAPHVq

Multiverse-Inventories is no longer being maintained. We have found a good replacement that even supports importing your inventories from MV-Inventories: PWI