You MUST have switches 1 and 6 UP for Online! to work correctly. Switch 6 UP
enables the Carrier Detect line so that Online! knows when a connection is
made. A lot of terminal programs require this switch DOWN which forces the CD
line to the ON state all the time.
Also, make sure that the suffix for phone numbers begins with the "|" (vertical
bar) character which in Online! always stands for a carriage return.
I assume you are using the commercial release version. The first beta-test
versions had a bug affecting this.