Aternos Server problem when installing a mod "Server Failed to connect to server Internal Exceptioan: java.net.SocketException: Conection reset"
So i have a server that mainly play Ice and Fire mod using Aternos and today i wanted to add a mod, Iron's Spell's and Spellbook (im using the Ice and Fire: Spellbooks) so i add the mod and the other mods that i have to add so i can play. But, when i try to join the server, this message (Server Failed to connect to server Internal Exceptioan: java.net.SocketException: Conection reset) keep popping up. So i tried many solution and it still happening (flush DNS, re-installing all the mod).
After all those failed attempt, i give up and just restoring my backup point that i always make before insalling a new mod. Surprisingly, without the Ice and Fire: Spellbooks, the server works and that message didn't popping again and i can join to my server. But, when i try to installing it again, that messsage popping up again everytime i tried to join the mod.
Can anyone help me with this?
Launcher: SKLauncher