Hi TheRob,
Thank you for your post. Our Help Article Sending emails using Microsoft Outlook has information and instructions on how to set this up, also if you're using Outlook 2010 there is some information provided about this issue on the Microsoft Support site which has information on how to resolve it.
Do let me know how you go.
If my response has answered your enquiry please click "Accept as Solution" to assist other users find this information.
Thanks for the reference. I tried the suggested setup last week but it didn't work. Even though I selected the default I wanted, it still sent from my personal email. I will try again next week when I send out invoices and see what happens.
