Sep 13 2017 12:31 AM
Sep 13 2017 12:31 AM
Our scenario is as follows:
Our client is on Exchange Online and using Outlook 2013. We have 2 people accessing a shared mailbox called Info@mycompany.com
PersonA and PersonB have access to the shared mailbox with full permissions. PersonA and PersonB are able to successfully send and receive from firstname.lastname@example.org
Send mail from PersonA@mycompany.com TO email@example.com, firstname.lastname@example.org
email@example.com and firstname.lastname@example.org receive the email - no problem yet
PersonA views the email in the Info shared mailbox and hits Reply All
Problem exists here where:
From = Info@mycompany.com
To = Info@mycompany.com, email@example.com
From = firstname.lastname@example.org
To = PersonA@mycompany.com, random@randomcom
Why would Outlook incorrectly remove PersonA@mycompany.com and incorrectly add email@example.com to the TO field (unecessary since you're replying from firstname.lastname@example.org, the shared mailbox)?
How do I configure Outlook to fix this?
Sep 13 2017 12:11 PM
Most likely becaus Outlook "sees" you as PersonA. So how exactly are you accessing the shared mailbox? This is the expecte behavior when you have the shared mailbox added as additional mailbox (via File -> Account settings -> More -> Advanced), as you are acting as the delegate. If you want the "correct" behavior, add it as additional account instead (File -> Add account -> enter shared mailbox address -> enter *your* username and password when prompted for credentials).
Sep 13 2017 10:41 PM
We're giving PersonA full permissions on that Shared Mailbox, which in Outlook means we don't add the mailbox at all, Outlook does it by itself.
Sep 14 2017 12:13 AM
So Automapping, got it. This is equivalent to the "additional mailbox" scenario, thus the behavior you are seeing. If you want the "correct" behavior, you need to add it as additional account instead.
Sep 14 2017 12:17 AM
From what you're saying it sounds like Automapping is optional? How do I switch it off and try what you're suggesting?
Sep 14 2017 12:25 AM
It's optional, but need to be configured via PowerShell. Remove the permissions and re-add them with Automapping turned off:
Remove-MailboxPermission mailbox -User delegate -AccessRights FullAccess
Add-MailboxPermission mailbox -User delegate -AccessRights FullAccess -Automapping $false
The mailbox will not automatically appear in Outlook then. To add it (as additional account), use the File menu -> Add Account -> Enter the shared mailbox email address and dont enter password. When prompted for credentials, enter the UPN/password of the delegate user.
Sep 14 2017 12:30 AM
Would doing this have any impact on our ability to convert the shared mailbox to a regular mailbox at a later date?
Sep 14 2017 11:11 AM
No, that's simply "client access" method, doesnt affect any of the mailbox properties.
Apr 21 2022 08:03 PM
May 05 2022 08:30 AM
We migrated to O365 in our organization and also in five customers organization.
Everyone has this problem with the standard O365 configuration and deploy settings, I believe there's no simple solution and everyone thinks it should be fixed.
We have single persons who owns mailbox in two or three domain of the same company, they obviously pay for just one account with two "shared" mailbox for them only (I do the same with two of our domains). The issue persists and they complain a lot, I hope some kind of fix will be available.