MAPI - Error - Profile not valid

Hello there! I am writing an application that automatically sends an email to the appropriate party based on certain criteria. I am using MAPI, but I want to use a specified email account to send the emails from. When I enter the user name and password into the properties screen of the MAPI session control and then try and send the email, I get an error message stating that the profile name is not valid and to enter a new profile name. I click ok, and my personal profile appears and if I click ok, it sends the email. But, it sends it from my email address, not the one I specified in the MAPI session control. Can anyone give me any pointers on how to get the specified email account to send the emails?

Thank you!