In Crelate, you may have multiple email connections in your database. The purpose here is to allow you to have multiple addresses that you may send from while indicating one specifically as your primary.
To start, select the main menu and Your Profile & Preferences
Afterwards, you'll want to navigate to the Email Connections section.
You'll notice in the screen shot below, there are two email connections. The connection with the highlighted yellow star will be your primary connection. To change this, simply select the non-highlighted star.
If you simply wish to send from a different email but do no wish to change your primary email connection, you may select your email address before attempting to send. This will pull a drop down menu below displaying all email connections that you have created or that have been shared in your organization.
Learn about what a shared email connection is and how to set up your email connection if you haven't already done so.