Unfortunately, Exchange still does not offer a convenient way to send emails to other email addresses. If users should be able to send mails with different e-mail addresses, additional mailboxes can be created and linked to the user.
Recently, however, I received a question about how a user can still send emails to multiple email addresses without having to create additional mailboxes. In this case, it was about a third-party software that is licensed per mailbox, so additional mailboxes would have required additional licenses.
To cut a long story short, it works without additional mailboxes, as distribution groups can also be used.
Here is a brief overview of the initial situation:
The user "Lucky Luke" has two e-mail addresses, each in different domains. In this configuration, Lucky Luke can receive emails with both email addresses, but can only send emails with the primary address (marked in bold):
The attempt to send an e-mail under an additional e-mail address fails:
If an attempt is made to send an e-mail to a different address, a corresponding undeliverability report is sent to the user's mailbox:
This message could not be sent. Try again later or contact the network administrator. You are not authorized to send the message on behalf of the specified user. Fehler: [0x80070005-0x0004dc-0x000524].
A distribution group can now be used so that Lucky Luke can also send mails under the e-mail address "frank@frankysweb.de".
In this example, a corresponding distribution group is created with the name "Frank Zöchling":
"Lucky Luke" will now become a member of this distribution group so that replies to mails will end up in Lucky Luke's mailbox again:
In delivery management, you can select whether only internal senders or also internal and external senders may send to the distribution group:
The new distribution group now receives the additional e-mail address. In this case it is "frank@frankysweb.de". If the e-mail address is already used as an additional address for a mailbox, the address must first be removed from the mailbox:
Finally, the user "Lucky Luke" is authorized to send e-mails on behalf of the distribution group:
The user can now send e-mails on behalf of the distribution group. To do this, the distribution group must be selected once from the address book:
The mail is now successfully delivered, replies to this mail will end up in "Lucky Luke's" mailbox again:
As already mentioned at the beginning, the route is not really comfortable.