Step 1. Account Settings
At the Gmail inbox, click the settings button on the upper right hand side of the page. Next, click "Settings" in the drop down menu that appears.
Step 2. Accounts and Import
On the "Settings" screen, click "Accounts and Import", then "Add a POP3 mail account you own."
Step 3. Adding an Account
In the yellow window that appears, enter your email address and click "Next Step," then fill in the fields on the next screen. Your username should include the domain. For example, "firstname.lastname@example.org" instead of just"demo." Ensure that "Port" is set to "110" and click "Add Account."
Step 4. Add SMTP Account
If you'd like to send from Gmail as the account you just added, click the "Yes, I want to be able to..." option and hit "Next Step." On the next screen, enter your name as you'd like it to appear on the mail you send in the future and click "Next Step." Finally, enter "smtp.sentco.net" in the "SMTP Server" field as well as your account credentials, then click "Add Account." Your Sentco e-mail account will recieve a confirmation code from Google in order to verify that you were the one that linked the accounts. That's it! You will now be able to send and receive e-mails from your Sentco account in Gmail!