Is Outlook Search > All Mailboxes just gone now?

Question

Morning all,

I've a user who unlike the rest of her org has only just been moved up to Office 365 from on-prem (all the other users were moved some time ago).

Following the move, this user has raised she can no longer select "All Mailboxes" in instant search in Office.
The user was previously able to use this to search the shared mailboxes she had access to.

Things I've checked:
-The "All Mailboxes" option is no longer present in the search dropdown
-"All Outlook Options" seems to never provide any results
-Outlook Options > Search > Include results only from: All Mailboxes does NOT make Outlook search do all mailboxes
-Having two mailbxoes added as separate accounts In oulook makes "All Mailboxes" come back, but that will only search the two mailboxes, not any shared mailboxes they have access to.
-I thought being in cached Exchange mode might make this work (It does bring the "all mailboxes" search back, but it fails to let you actually search shared mailboxes.

Is this feature just no longer available?

I'd be happy to tell the user they're out of luck but would rather be sure I'm telling her the truth.

Cheers

Paddy

Answer 1

I believe that is the case and is a known issue:
https://support.microsoft.com/en-us/office/troubleshooting-outlook-search-issues-2556b11f-f4d8-46be-b0a7-de33a3f4f066#:~:text=No%20results%20are%20returned%20if%20you%20use%20the%20All%20Mailboxes%20scope

Answer 2

Thanks Andy, at least I have a definitive answer.

I shall attempt that workaround for the user.