Nodes in SCOT show status "off" !?

Hi!

I'm trying to set up SMTP for incoming mails. If I go for transaction SCOT all nodes show me the status "off". The sub-node "INT" of "SMTP" also shows "off" when changing to view "Nodes". I already configured the "SMTP" node and ticked also the box "node in use". Can anyone give me a hint!?

Cheers