Historically, Exchange has used a user’s primary SMTP address as the From address when sending messages. Other SMTP addresses assigned to a user (e.g., proxy addresses, also known as aliases) were ma...
Updated Oct 21, 2024
Version 11.0
Blog Post
Hi Victor_Ivanidze,
With the new feature, Outlook automatically sends using the alias through which it received the message.
Quoted from this article by Microsoft.
"Aliases will also be preserved when messages are addressed to them. If a user replies to a message that was sent to their alias, their reply will come from the alias by default."
The first use case occurred in March 2023 when the first user reported the issue. We explained to the user, as described in this article, that they needed to enable the alias in Outlook to send through it. Following those instructions resolved the problem. However, since the latest Office updates, this method no longer works. When checking for solutions in this article, it states that "send as alias" is not supported for Shared Mailboxes.
"For shared mailbox, send from alias feature works only with OWA when delegate opens it using “Open another Mailbox” option. For Outlook client, send from alias feature is not supported for shared mailbox which is either automapped or added to a profile as an additional mailbox."
Yes, ours user cant send over Shared Mailbox with alias in Outlook Desktop Client