I need to add a second domain for a group of users with separate From email address.  When email comes in to a distribution group, they will all receive the emails.  When they respond to that email with different domain name, how can Outlook automatically use the same domain's alias?  Does need to be manual every time the user respond to the second domain emails?

Email comes into info@test1.com

info@test1.com is a distribution group that send to user 1,2,3

user 1 respond to the email, the from address needs to be user1@test1.com

The native solution is to create a separate mailbox for the different e-mail address and populate the From: address when replying from it.

The third-party solution is Ivasoft's ChooseFrom.

http://ivasoft.biz/choosefrom2013.shtml

Hi JT_CP,

Thank you for your question.

By default, every mailbox could have multiple emails address, but it just has one email address as primary email address, when we reply email, we just use the primary email address.

For example:

If user1 has two email address, the one is user1@test1.com which is primary email address, the another is user1@contoso.com. In addition, the user1 belong to distribution group which is info@test1.com.

When email comes into info@test1.com from @contoso.com, the user1 could receive email, but user1 just use the user1@test1.com as reply email address.

If there are any questions regarding this issue, please be free to let me know.

Best Regard,

Jim