Isutiger89,

When sending any message, you are only allowed to send as SMTP addresses you have configured in your Outlook profile. This means if you have 2 accounts, say gmail and a yahoo account, you will only be allowed to send as these accounts.

Outlook does not have an automatic function that will allow you to send as the received address especially with a profile configured with multiple accounts. However, outlook does allow you to set one as a default, this will be the one that is selected as the Primary SMTP address and used to send each time. Any other accounts will have to be manually chosen.

*** You can set up rules to automatically reply using a template response. This however does not sound exactly what you are asking for. Any other rule construction to reply directly to any email scenario will use the defaulted email address.

Hope this helps.