Additional notes

Owned by Mike Harrison
Last updated: Jan 31, 2024 by Andy Brook [Plugin People]
3 min read

Support for multiple recipients

As many customers using Microsoft 365 with JEMHC will potentially want to use Project Mappings where the address is used by JEMHC to route mail to many projects through a single pickup mailbox, the options are as follows:

Sub addresses

As per https://thepluginpeople.atlassian.net/wiki/spaces/JEMHC/blog/2020/07/14/1817444372 this is reported to now work but doesn’t “just work”:

Some Powershell twiddling as admin is needed to enable:

Set-OrganizationConfig -AllowPlusAddressInRecipients $true

Apparently this still only works with mailboxes, not for DL/group addresses.

Account Aliases

As of August 2020, Microsoft 365 appears to support mailbox aliases: https://docs.microsoft.com/en-us/microsoft-365/admin/email/add-another-email-alias-for-a-user?view=o365-worldwide

Email Aliases in Microsoft 365 take 24 hours to become valid, prior to this they will be rejected (shown below).

O365 Doesn't always retain the inbound Alias address

O365 doesn't yet support the ‘Delivered-To’ header for Alias addresses (even when the mail is routed correctly, JEMHC has no way to determine what that Alias is, reliably).

Anecdotal comments from a customer using o365:

… Exchange Online is writing the To: header differently based on if the message is sent internally or externally. Messages sent from inside our Exchange organization always get the primary SMTP address, while messages sent from external senders write the actual address.

Retaining in the incoming address in outbound mail

You may also want to retain the incoming address for use in all outbound notifications. The support for Aliases, as covered in the prior section is not not guaranteed, in such cases, all you get is the common primary mailbox address. We encourage o365 customers to engage with MS support on this topic.

JEMHC can store inbound address in a Custom Field default

  1. Storing the $catchemail (see end of : )

  2. Using the custom field during sending:

We found the following on the web (cannot really dig more into o365 mail configuration):

Apparently, the ability to “send email from alias addresses to the Outlook Web App“ is on their roadmap, it may take a while to become real (its listed as DEC 2020…) by comparison, Gmail GSuite/Apps support for this ‘just works’:

The ability to send email from a proxy address (aka alias) other than the sender's primary SMTP address is useful in multiple scenarios, such as mergers and acquisitions when you need the to send from multiple branded domain names, or sending on behalf of a team or department, like info@contoso.com. And of course, having the FROM and REPLY TO boxes preserve that alias when the recipient sees it is just as important. So to kick-off our journey to provide you and your users with the flexibility to send email using alias, we're excited to announce that soon Outlook on the web (aka OWA) will natively support the ability to choose the sender or FROM from a drop-down list right within the compose pane. And when the recipient receives that message, the FROM and REPLY TO will show that alias, regardless where the recipient's mailbox happens to live.

  • Feature ID: 59437

  • Added to Roadmap: 12/5/2019

  • Last Modified: 8/21/2020