Welcome,

In january 2018 I had an old world which i was using since 2011. Unfortunately, happened something wrong. In fabruary 2018 I upgraded world to new snapshot and then the world broke down- i dont remember what's happended... Now the world had new chunks and my virtual city destroyed. Maybe I can repair this?

But the main thing now is upgrading copy (from January'18) of this world from 1.12 version to 1.15.

I've done it. I've choosen optymalization tool and the world started. Its seems to be okay, but:

• Chests cannot open
• Statystics cannot open
• The world is loading very slow and some of chunks are not loading
• The game don't close, all the time "saving world" text
• Commands don't work
• Few cosmetical problems like: not correct signs's texts, for ex.; before new version: "TEXT >" after: " /'TEXT;' "

Please help me