hello community

opensuse install but I have some problems. web access by income http://localhost/ox6/ox.html testuser secret click ok but the e-mail message.
Unable to establish a connection to the E-Mail server. Possible reasons: the mail server is (temporarily) down or there are network connection problems. To prevent further errors the module has been disabled. Please contact your administrator.
another at the time of the installation never went to to put the domain mydomain.com as does the server know which is my domain and how to activate the e-mail