because the server isn't on
Client outdated means that the client (the software used to connect to the server) is out of date. You need to update your version of Minecraft.
If it says outdated client, it means the server is at a newer version than you are. You need to update your game to be able to play on the server.
A. The PTR resource record.
Either the server needs to update or you need to update.
you cant you have to connect to the enternet if you have access
Generally, because the server is offline, or the cache isn't valid with the client you're running
dynamic
The "Could not connect to server 127.0.0.1 connection was refused" message in Thunderbird typically indicates that the email client is trying to connect to a mail server running on your local machine (localhost) but cannot establish a connection. This could be due to the mail server not running, incorrect server settings in Thunderbird, or firewall issues blocking the connection. To resolve this, ensure the mail server is active, verify the server settings, and check your firewall configurations. If you're using a remote server, update the server address to point to the correct external IP or hostname.
It usually means the server version is older then your game version. Every time Minecraft updates they usually update the server also.
delete a mod maybe and force the update?
You update your minecraft or get the older version. If your minecraft version doesn't match the server's version, then you can't join it no matter what you do.
There may be several reasons you would be unable to connect to your own server on Minecraft. First check to make sure you have not typed in the Ip address wrong. Second, make sure you are running the latest Minecraft server software(You have to download a new version after every Minecraft update). Thirdly, you cannot connect to a server using the computer that is running the said server.