619 is probably Aol's own error message, and I'm afraid means nothing to me.
If you are at the sign-on screen and both arrows on the task bar are dark green then try -
'Sign on options' and choose 'Expert setup'.......Then choose 'Add location'
Give it a name ("Home 2" say) and see what follows. The answer is in that region somewhere. ....... If desperate you could try 'Add a Modem' but try the location routine first.
Sometimes the human support is a little underexperienced or unenthusiastic! I think sometimes they pick an idea and just read from a prompt sheet.