Queen_V

I have been playing for the past few months off an on. Just this past week I noticed that while I am playing tekkit logs me out and most of everything I was working on is gone. If my inventory isn't gone then my entire world is gone. Tonight I was crafting and as I was trying to move things from my inventory to the crafting table or vise versa, it logged me out and then upon logging back in all the items I was using were gone. What is up with this?