Every time I power on my HTC S740, I get same greeting: "The operator does not exist in the database. Please contact your operator for the connections settings. Connection Setup will redirect you to the Connection screen". Once you select Hide as menu option, redirection to Settings\Connections does happen and you have your chance to define connections. Once you define connections, this screen will not appear again. That is how things should look like.
Probably I am problem here.
When I am traveling somewhere I like to delete all data connections. That is sure way to avoid roaming cost. However, when you delete all connections, Connection Setup screen reappears after every power-on. If I am traveling via plane, with few boardings in between, power-off and power-on cycle happens quite a few times and "The operator does not exist in the database." gets boring pretty quickly.
Solution is quite simple but not obvious one. Turning that setting off is not done in Settings/Connections which, in my personal opinion, should be place for this. On HTC S740 you need to go into Accessories menu and there you will find Connection Setup. Once you run it, under Menu there is option "Enable Auto Configuration". Uncheck it and you will not be bugged any more.
Hint to HTC - once user selects Hide, do not bother him again unless he changes his SIM card.