With a catch all , you don't have to worry about setting up individual pop mail accounts. Simply set your email client to your "default" email address (displayed in your control panel), and "all" email sent to anything@your_domain.com will land in this box, or whatever you've set your default address to. This is an easy way to catch all email sent to your domain.

In your Email client, feel free to configure multiple outgoing accounts at different-names@your_domain.com. It really doesn't matter, as everything@your_domain.com will land in the default account. Therefore, you would configure all of your email accounts with the "same" Username and Password as your "Default domain Email Account."

Caution: often setting a catch all account means your domain will catch the random names spammers use when mailing people hence you will receive more spam.