

BUT, this won't help if you need to add From addresses from multiple host servers. The only work-around I know of is to delete the Outlook profile, add the first server, use all the From addresses so they populate the drop-down list, then and only then, add the other servers. I have tried searching the Registry and "%localdata%\Microsoft\Outlook" but have not been able to find where these values in the drop-down list are stored to add to it. For more information, ask your admin to see Create a shared mailbox, which describes what the admin needs to do. It is impossible, as far as I can tell so far, to add any more now because there is more than 1 server in the top block: From the document you shared: Tip: Before you can use a shared mailbox, the Microsoft 365 admin for your organization has to create it and add you as a member.

In this case, you can see 3 servers above the block horizontal line in the drop-down plus 3 additional From options below that line. Is there a way to force them to "stick" and appear in the drop-down in the future? However, once you add a second server, then future selections from the Other Email Address never add to the drop-down.

Click on Open The shared mailbox should show up then on the left with all of your e-mail folders as well. Enter in the Shared Mailbox name or its full e-mail address 4. Select the shared mailbox from the list of results and then click Add. Click on File then Open, followed by Open Users Folder. In the Choose a Person window, start typing the name of shared mailbox in the search field. In the Open these additional mailboxes section, click the + (plus sign). With only one server, selections from the "Other Email Address." selection generally (not always) do stay in the From drop-down. In the Accounts advanced settings window, click the Delegates tab. Ivanidze, this is only true if you have a single Exchange connection.
