Avatar of Rick Goodman
Rick Goodman asked on

Adding second Send As domain to Exchange Server

I need to add a second send from domain to my Exchange server. From what I understand, I need to a second send connector for that domain. I currently have a trusted SSL certificate for the primary domain installed on my CAS/HUB servers. Do I add the new domain to my existing SSL certificate or do I need to add second certificate with the new domain, thus giving me two separate SSL certificates. Also, do I just run an EdgeSync after this is all done to sync the Edge Transport server? Any other input as to what else I may need to do would be welcomed as well. Thanks in advance all, any help would be appreciated.

Avatar of undefined
Last Comment
Rick Goodman

8/22/2022 - Mon
Mohammed Tahir

You can not add new domain name to existing SSL certificate, the only option is to create new (second) SSL certificate for new domain.

Simon Butler (Sembee)

The above is incorrect.
Your existing SSL provider will usually allow you to add additional domains to the SSL certificate. Sometimes this is free, other times not.

You need to speak to your provider.

The only name you really need added to the certificate is autodiscover.
End users can use the existing names for everything else.


I don't think you will need another SSL cert at all unless you are changing the OWA page as well. I would just redirect all requests to your current domain though to save some money. You should be able to just add the domain to your accepted domains list and set the primary reply address to the new domain. Otherwise you should be good to go.

If you want users to have a different UPN for logging into OWA you can add the domain to your domain and trusts Alternative UPN Suffixes.

For autodiscover you can use an SCP record to avoid getting another cert or do a redirect site for all autodiscover requests.
Experts Exchange has (a) saved my job multiple times, (b) saved me hours, days, and even weeks of work, and often (c) makes me look like a superhero! This place is MAGIC!
Walt Forbes
Rick Goodman

I'm not sure I can just redirect them, they want all email they send to be sent and appear to be sent from the new domain. I will likely have to have OWA and autodiscover to work. These are users that will work on laptops from the primary domain but will need to send and receive their email from the newly added domain, which used to reside on another mail server at another company.
Simon Butler (Sembee)

Log in or sign up to see answer
Become an EE member today7-DAY FREE TRIAL
Members can start a 7-Day Free trial then enjoy unlimited access to the platform
Sign up - Free for 7 days
Learn why we charge membership fees
We get it - no one likes a content blocker. Take one extra minute and find out why we block content.
See how we're fighting big data
Not exactly the question you had in mind?
Sign up for an EE membership and get your own personalized solution. With an EE membership, you can ask unlimited troubleshooting, research, or opinion questions.
ask a question

Sembee is correct. Your users should be just fine with having their owa page as domainA.com/owa even though their email is domainB.com. Like i said you wanted to do a redirect they can go to domainB.com/owa and it will just redirect them to domainA.com/owa. Your users will still send and receive as their domainb.com address and all external users will not know any difference. As a hosting provider this is how we host other companies emails for about 200+ companies.
Rick Goodman

Sembee, I understand it routes email based on the recipient, but if I add domainb.com as an accepted domain, can't I just add a second send connector and configure it with a new SMTP address space for domainb.com along with an MX record pointing to my mail server and an A record pointing mail.domainb.com pointing to may mail server for reverse DNS? Or is that too simple?
Get an unlimited membership to EE for less than $4 a week.
Unlimited question asking, solutions, articles and more.

You do not need to create another send connector. Send connectors do not route based on source domain only on destination. So you would not need to create one coming from your exchange box. If you wanted to route all gmail.com traffic going out then you would need another send connector.

here is a link to some info on send connectors.
Rick Goodman


Thanks. I think I got it now. So it sounds like I just add domainb.com as an allowed domain, have an MX record pointing that domain to my server, and then add that email address and select set as reply for each user account. If I'm right, thats way easier than I was trying to make out to be.
Log in to continue reading
Log In
Sign up - Free for 7 days
Get an unlimited membership to EE for less than $4 a week.
Unlimited question asking, solutions, articles and more.
Rick Goodman

Great job, that was very helpful.
All of life is about relationships, and EE has made a viirtual community a real community. It lifts everyone's boat
William Peck