started an all the mods 8 server and it crashed when i joined

[green harbor]

19.09 00:07:23 [Server] Worker-Main-54/[WARN] [ModernFix/]: The namespace betteroceanmonuments contains an outdated structure file, which can cause worldgen lag. Please view debug.log for the full filename, determine which mod provides the structure, and report to the mod/datapack author, including the debug log.

[chilly marten]

Please send complete logs of the console. Based on what it says, this does not feel like an error.

[loud void]

You should contact the modpack author as it’s there modpack so they have to fix it

But send them the entire log yes