Unable to enter Minecraft server friend is on as it's down for maintenance [closed]

Solution 1:

1) Since your friend can connect the server is up

2) You connect to some different server that says it is under maintenance

Make sure you both connect to the same server (IP-Address!). I assume that you connect by host name, and further assume that the server was under maintenance a few minutes or hours ago, when you tried to connect.

DNS requests are cached, so it's possible that the hostname you try to connect to is leading you to the wrong IP (the one that is used while a server is under maintenance). Try refreshing the DNS cache (https://superuser.com/a/80758/138216)