Customizing Allowed Versions

To prevent exploits, only a few of the latest versions are set up to be able to join your Minecraft Server Setup. If you'd like older versions to join, you can configure specific versions or a range in the ViaVersion config.

Navigate to the file /plugins/ViaVersion/config.yml and open it. Around line 18 you should find a block-versions key. You can either modify the versions here yourself, following the explanation comment above, or use this calculator to easily get a list of versions/protocols to block.

After you've made your changes, save the file and run /viaversion reload to apply them.