mojira.dev
MC-307418

The game crashes when trying to upgrade a legacy world

Hello,

ISSUE

I am having an issue with upgrading my legacy world (created in 2014/2015) to the new 26.1 world format. The latest version of the world is 1.21.11, and I have tried upgrading it using 26.1, 26.1.1, and the latest version, 26.1.2; I have had no success with these versions. When attempting to upgrade the world, it begins the process but consistently crashes the game when the loading bar hits approximately 85% completion when “upgrading legacy structures.” The screenshot of the crash has been attached to this post.

WORKAROUND

From my testing, removing the following files from the /data/ folder resolves the issue and allows the world to upgrade: Fortress.dat, Mansion.dat, Mineshaft.dat, Monument.dat, Stronghold.dat, Temple.dat, and Village.dat. I’m unsure if it is either one or multiple of these files that cause the issue, but removing all of them seems to have corrected the issue. However, I do not believe this is a reliable long-term fix as players should not have to manually delete world files to upgrade their world.

NOTE: I am using a purely vanilla world and client. I have no datapacks or mods within the world, and my launcher is unmodified.

Attachments

Comments 4

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[media]

We do not have enough information to reproduce this issue.

Please attach the affected world folder, compressed to a ZIP file. If the file size is too large, please upload it somewhere else and then link to it here.

This ticket is being temporarily resolved as Awaiting Response. Once the requested information has been delivered, the ticket will be reopened automatically.

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Hello,

I have attached the problematic world to this post. This world has been sanitized of all personal information that the world originally possessed (this is a public forum after all). This world exhibits the exact same behavior as described in my initial bug report. Let me know if you need any additional information. Thank you.

[media]

Can confirm that when upgrading this world using 26.1.2, it produces the error. I have also attached the log showing this error.[mediaInline]

Henry

gegy

Confirmed

Platform EC

Very Important

Crash, Datafixer

26.1 Snapshot 6, 26.1.2

26.2 Snapshot 7

Retrieved