How to Setup SMTP Authentication in Outlook
Open Outlook
Click on Tools at the top of the window.
Click on E-mail Accounts from the drop down window.
A window similar to the one below should open.

Click "View or change existing e-mail accounts."
Click Next.
There will be a window similar to the following;

Next, highlight the redred.com account and click on the Change button.
Another window will open similar to the following;

Click the "More Settings..." button.
Another window will open similar to the following;

Check the box labeled"My outgoing server (SMTP) requires authentication"
Make sure "Use same settings as my incoming mail server" is selected.
Click OK to close this window.
Click the "Next" button in the E-mail Accounts window.
Click "Finish"
Done!