Only works on client but not the server?

Because this being called only on client, user presses J and all you do is call print on client, there no replication point where this action could be send out to server and then propagated to other clients. You should make replicable function to server and then make server call function that will make message display on clients, server could also process incoming message and decide who getting it. Also not sure if Print text counts as chat you enabled.

The client is working fine but the server is having none of it, what is wrong ?

I dont think he asking about replication and RPC. I think it about “input not work on server”. I have same problem before, but i dont remember how i solve it

yes Detech.

When I press J using server window it does nothing, when I press J using client window - it works.

detech please could you check your code to see what you added ? I put a switch has auth after pressing J and now clients can not press J. There is something definitively going on with server mode.