Office 365 Email Question

Soldato
Joined
1 Nov 2007
Posts
7,020
Location
England
I currently have an Office 365 subscription with one domain name already added to it. I want to add another domain because there might be some new users coming on board that need email addresses for that domain.

I was wondering in Outlook 365 if I give myself a second email address with the second domain name how I can choose whether to send the email from the primary domain name or whether I send it from the secondary domain name? I can't work it out at the moment but maybe I need to add the second domain before the option appears in Outlook 2016. I don't really know.

Any help is appreciated :).
 
Or, just add the secondary email address as an Alias in O365 and in Outlook enable the "From" option dropdown so you can choose which email address the email comes from. That's the more sensible option but as it's an Alias, emails to both your domains will appear in the same mailbox so when replying you just need to make sure which email the sender sent to is the one you reply from.
 
Or, just add the secondary email address as an Alias in O365 and in Outlook enable the "From" option dropdown so you can choose which email address the email comes from. That's the more sensible option but as it's an Alias, emails to both your domains will appear in the same mailbox so when replying you just need to make sure which email the sender sent to is the one you reply from.

Cool. Thanks. I did do some reading and it said that Outlook 2016 does have a From box but I couldn't find it for the life of me. That explains why. You need to add the second domain.
 
Cool. Thanks. I did do some reading and it said that Outlook 2016 does have a From box but I couldn't find it for the life of me. That explains why. You need to add the second domain.

New Email > Options Tab > Click From

This add the "From field" to the current email you're sending. All future emails you send will now automatically come with the from field in place.
 
New Email > Options Tab > Click From

This add the "From field" to the current email you're sending. All future emails you send will now automatically come with the from field in place.

Awesome. Thanks. Trying to find all the available options in Outlook 2016 is a bit of a pain.
 
Or, just add the secondary email address as an Alias in O365 and in Outlook enable the "From" option dropdown so you can choose which email address the email comes from..

Unless 365 is somewhat different from on-premise that won't work. The From field can only be used to send from different mailboxes, aliases are for receiving only.

Add the domain, create a DL with your account as the only member, grant yourself send-as permissions.

Or to keep everything separate simply create a shared mailbox which doesn't use a licence, assign yourself Full Access & Send As rights and then send/receive using that. You'll need to make a quick registry change so that emails sent as the 2nd account go into the correct sent items folder when you're in Cached Mode

https://support.microsoft.com/en-nz...items-folder-of-the-shared-mailbox-in-outlook
 
Unless 365 is somewhat different from on-premise that won't work. The From field can only be used to send from different mailboxes, aliases are for receiving only.

No, you can simply enter the email address and it does a lookup. If that's an alias, it will allow you to send from that mail. It's been an On-Prem option and O365 option since as long as I can remember and I use that method daily.

And you don't need to do any reg changes for Shared Mailboxes now in O365, the option is now a tick box in the O365 Shared Mailbox settings (not through the Exchange Admin Console) so that messages appear in the sent items folder of the shared mailbox
 
Last edited:
That definitely changed recently (as in within the past 18 months or so) if that's the case. I've always had to use the DL workaround.
 
No, you can simply enter the email address and it does a lookup. If that's an alias, it will allow you to send from that mail. It's been an On-Prem option and O365 option since as long as I can remember and I use that method daily.

This must be new with 2016, we've only recently migrated from 2010 in the past few months and it certainly didn't work there. I've just tested it internally and once it's replicated through our DAGs it's worked, just waiting for our anti-spam to update so I can test externally. If this works it's going to save us a lot of hassle haha!

That definitely changed recently (as in within the past 18 months or so) if that's the case. I've always had to use the DL workaround.

Seems to be a 2016+ thing, not sure if it was present in 2013.


EDIT: Just tested this externally and I still get my primary SMTP address, the alias thing only works for internal mail.
 
Last edited:
Well, it works for me, and I've been using it for quite some time.

Can you provide some more info as to what you're using to achieve this and perhaps provide a message header?

I can technically send as an alias, but it's not presented that way at the other end it simply associates the primary email address.

We run 365 E3 / Outlook 2016, without AD Sync.
 
So I have two domains in O365. Domain 1 and Domain 2, both verified and the corresponding DNS values set.

To avoid using two licenses, I have one user who's primary SMTP is domain 1 ([email protected]) and also has an smtp value for domain 2 [email protected] (alias).

In outlook, if I receive an email to [email protected], I can reply "from" [email protected] and that is what the recipient sees. Although it falls into my sent mail folder (domain1).
 
Back
Top Bottom