If you talk to email service providers they will usually tell you that their system is 100% compatible with everyone elses, however many people find that they are unable to send emails to all of their friends and relatives.

For example many people find that they have problems receiving emails from Terra or Telefonica email addresses this is because Terra and Telefonica have been blacklisted by many email providers as being sources of spam. The only simple solution is to setup an alternative email address that is compatible with your friends server, usually one of the larger well know companies will do such as GMAIL, Hotmail or Yahoo.

All three are free services and are online accounts although Gmail can also be setup to work with Outlook, Mail or Outlook Express. The paid Hotmail email address also have this facility.