An error occurred during the world update from version 1.21.11 to version 26.1.2

Thank you for helping us improve Minecraft! We saved your files:

I found archive of this World from version 1.18.1 and I still get the same error when I open it in version 26.1.2

The attached files are corrupted. Please attach a working ZIP file.

_{This issue is being temporarily resolved as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.}

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Sorry, the file size was bigger than 100MB so I split it and that's probably why you couldn't open it. Try downloading from the dropbox

https://www.dropbox.com/scl/fi/1vo3500e7yl95l4b4aggm/2026-06-01_20-34-36_MyNewWorld.zip?rlkey=bi0kgrzg05nh2f87lbaicynkh&st=fxitqdwx&dl=0

Thank you for your report!
However, this issue is Invalid.

This report does not describe a bug.

Your world contains files from a modified version of the game. The file that prevents the world from being upgraded seems to be the one in the "data" folder just called "minecraft" with no extension.

Quick Links:
📓 Bug Tracker Guidelines – 💬 Community Support – 📧 Mojang Support (Technical Issues) – 📧 Microsoft Support (Account Issues)
📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki

Thank you for help you’re right