The Gigamail requires the same configuration as the other domain email accounts on mail Clients. With it, you can also activate the Antivirus & Antispam service.
Here below are the parameters you must use to configure the email client
Incoming mail(POP3): pop3.domainname.xxx
Outgoing mail(SMTP): smtp.domainname.xxx (only if you connect using Aruba.it or if you use the Antivirus & Antispam service)
Account Name: email@example.com
Password: the one you selected for the account
Attention: you can only use the outgoing mail server (SMTP) related to your domain if you connect through Aruba.it, if not you need to contact your ISP.
See the guides for the configuration of email clients at: http://kb.aruba.it/KB/c673/caselle-domini.aspx