I run a Minecraft 1.17.1 server on the same machine but when I try to connect to it I can't, while everyone else can join it. I'm connecting to localhost:"port". When the server was still in 1.16.5 it worked just fine. I have my firewall disabled.
This is the error that I get when I try to join.
I think it is some kind of client issue because when I try to use 1.17 to connect to the server (that is in 1.16) I get the same error, not the outdated one.