Learn more about this change here.
For help regarding Aternos, we recommend you to visit our support center.
Do you face the same problem if you try to connect to a Vanilla server with the Vanilla client?
Then the problem is probably caused by the mods or your mod loader (Fabric).
The Aternos system only wants you to delete the world/reinstall the server if the software you want to install is known to be incompatible with the software you currently have installed.
This is intended behavior to protect users from corrupting their server data.
A workaround you can do the following to keep your world:
- Stop your server
- Download the world on the worlds page: https://support.aternos.org/hc…35711-Download-your-world
- Switch the software
- Upload the world again: https://support.aternos.org/hc…0027235751-Upload-a-world
Please note that Aternos has an upload limit, which is explained in the guide for the upload. If your world is larger than this limit you can't upload the world again.
Also understand that doing this procedure is not recommended and that Aternos cannot provide any further support about it. Worlds which were used on a modded server can cause issues if you use it on a server with another software. This is also the reason why the system wants you to reinstall the server.
Then it's your world/mods. If you can join a Vanilla server then it's not a network problem.
