Fatally missing registry entries (ExtraAnvils mod)

Hello, I am making a modded server.

When I try to join my server, I get disconnected with the message "Fatally missing registry entries." (Log: https://mclo.gs/8dYw1fN [when I last joined the server was on line 2506)

In the logs, they show "Attempting connection with missing mods [ctgui] at SERVER."

Quote from Adriel

extraanvils doesn't match.

You need the same mods in the exact same versions on your client and server.

Thanks for the help. I saw this was the answer to a question when I was searching other questions, but I think I got it mixed up with another mod. Either way, your answer reminded me to double-check, which made me figure out the problem.