When you are connected to a network, of course $server will return the name of the server you are connected to, respective $network.

When you get disconnected or quit/close the connection, the $server and $network identifiers must be $null.. but sometimes, being disconnected, $server and $networks remain filled with previous data!

This is rarely happened to me and I don't know how to reproduce this again, but it happens rarely.

Thanks for your bug report.

The $network identifier may return a value whether connected or not. It depends on whether mIRC has found a network name from your servers list, and so on.

However, the $server identifier should only return a value when connected. There are some situations where it will return a value after disconnecting, for example during the on DISCONNECT or CONNECTFAIL events. But I have not been able to reproduce an issue with $server returning a value while disconnected yet.