Quote possibly the Perform section in mIRC. It was moved to a different area of the options dialog is mIRC 6.1:
ALT+O > Connect > Options > [Perform..].
If you want it to trigger on individual networks click on 'Add' and choose a network from the list, then put the commands in there. That way, when you connect to the network you specified the commands will be executed only on that network, not if you connect to others.
Less likely but possible, you may have used mIRC scripting. See
/help on connect.
Hope this has refreshed yew
Regards,