Exchange shared mailbox

Vertigo · 27 Apr 2017 at 11:05

Have set up a shared mailbox on Exchange 2010 but am having problems with the infernal from address.

I've configured the mailbox as an additional account within Outlook so it appears as a totally separate mailbox. Now it all works fine for me - if I have the inbox of the shared mailbox selected when I create a new email, then the from address is preset to the address of the shared mailbox which is what I want. However if other users do the same, they get their primary mailbox address instead.

Now I'm the domain admin so I'm suspecting there's something different in my case but I can't figure out what. All users have full access and send as permissions on the mailbox.

What am I missing? Why does it work for me but not others? Trying to Google this is hopeless as every site you find is simply telling you how to configure the shared mailbox so the from address works correctly, not telling me what to do once I've done this but it's not working for some users.

Caged · 27 Apr 2017 at 19:35

Are you sure the permissions are right? If you have granted send on behalf by mistake then your users will only have that right, if you're a domain admin (please say you aren't using that as your daily account) then you have SendAs without anything else needing to be granted.

If you issue is about not being able to pick the account in Outlook, get your users to compose a new message, go to the options tab and click 'From' in the show fields section. Use the dropdown to pick the from address out of the GAL. This only needs to be done once.

nightmare99 · 28 Apr 2017 at 08:17

Is there shared mailbox auto mapped for the other users?

I suspect you will need to do this https://support.microsoft.com/en-nz...items-folder-of-the-shared-mailbox-in-outlook

EDIT: Apologies, I didn't read the OP correctly this is not what you want. Use the from field as per caged above.

16-bit · 28 Apr 2017 at 11:03

There's three ways to send as another account:
Using the from address mentioned above.
Replying to an email inside the shared mailbox.
Adding the other mailbox as a separate account.

@Caged, Domain admins don't have send as by default IIRC.

Toughnoodle · 28 Apr 2017 at 14:58

I think you also have the issue where replies go into the default mailbox sent items instead of the shared mailbox (although there is a reg hack for it). I tend to set up shared mailboxes like I would any other, set a complex password, never expires and add them to Outlook as another account. I think Outlook has been able to handle more than one Exchange account since Outlook 2010.

Nicholas Eagle · 29 Apr 2017 at 22:21

To the OP question, Are there any differences between your clients that are being used. You say that Exchange 2010 is being used but this sounds more like a Client configuration that would be causing which default address should be used by default.

To the following, pretty bad practice to be honest Share Mailboxes should be disabled.

Toughnoodle said:
I think you also have the issue where replies go into the default mailbox sent items instead of the shared mailbox (although there is a reg hack for it). I tend to set up shared mailboxes like I would any other, set a complex password, never expires and add them to Outlook as another account. I think Outlook has been able to handle more than one Exchange account since Outlook 2010.

Assuming the shared mailbox is setup correctly as a 'shared' mailbox in exchange the account should be disabled by default.

I'd suggest using PowerShell to configure the access and in fact the shared mailbox its self.

Add Access permissions, Cmdlet - Add-MailboxPermission -Identity <ShareMailboxAlias> -User <UserAlias> -AccessRights fullaccess -InheritanceType all -AutoMapping $True
Add SendAs Rights, not to be confused with SendOnBehalf, Cmdlet -Add-ADPermission -Identity <ShareMailbox> -User <User> -ExtendedRights 'Send-As'
Outlook
- In Outlook if responding to an email that is in the shared mailbox this should work as intended.
- If sending a new email before any other actions, select From and find the shared mailbox in the GAL (the first time)
- Also good to check to ensure they have no autocomplete's in there outlook for the email address that is used.

Vertigo · 3 May 2017 at 15:58

Apologies for not getting back here sooner. To respond to some of the questions...

Caged said:
Are you sure the permissions are right? If you have granted send on behalf by mistake then your users will only have that right, if you're a domain admin (please say you aren't using that as your daily account) then you have SendAs without anything else needing to be granted.

I've granted both Send As and Full Access permissions on the shared mailbox to all the relevant users. I know my own account shouldn't be a Domain Admin but yes, I'm afraid it is right now. I'll sort that at some point.

If you issue is about not being able to pick the account in Outlook, get your users to compose a new message, go to the options tab and click 'From' in the show fields section. Use the dropdown to pick the from address out of the GAL. This only needs to be done once.

To clarify, I have the From field enabled in Outlook. If I have my own mailbox selected when I create a new email, the From address defaults to my mailbox address. If I have the shared mailbox selected, it defaults to the shared mailbox address. In each case I can change it if I need to but I don't as it's defaulting just as I want it. With other users, the From address defaults to their mailbox address even if the shared mailbox is selected. They can use the drop-down to change it but they'll never remember to do that every time so I want it to default as it does for me.

nightmare99 said:
I suspect you will need to do this https://support.microsoft.com/en-nz...items-folder-of-the-shared-mailbox-in-outlook

EDIT: Apologies, I didn't read the OP correctly this is not what you want. Use the from field as per caged above.

Toughnoodle said:
I think you also have the issue where replies go into the default mailbox sent items instead of the shared mailbox (although there is a reg hack for it).

I'm aware I'll need to do that via the registry tweak but I need to sort my main issue first.

Nicholas Eagle said:
To the OP question, Are there any differences between your clients that are being used. You say that Exchange 2010 is being used but this sounds more like a Client configuration that would be causing which default address should be used by default.

As above, that's exactly the problem, mine defaults correctly but other users don't.

Nicholas Eagle · 3 May 2017 at 16:13

So can you advise on what version of Outlook that is being used? 2010/2013/2016 x86/x64 also are all updates the same on both systems as working in IT I'm always more up to date than everyone else.

#Chri5# · 3 May 2017 at 16:32

Outlook 2010 onwards works with multiple Exchange mailboxes fine. In our experience it's best to disable the automapping (either via ADSIEdit or by giving the initial Full Access priv's by PowerShell (2010 SP2 onwards) rather than the EMC):

https://www.petri.com/disable-outlook-auto-mapping-for-users-with-full-access-permissions
ADSIEdit : http://www.stevieg.org/2010/08/auto-mapping-shared-mailboxes-in-exchange-2010-sp1-with-outlook-2010/

Vertigo · 3 May 2017 at 16:48

Yeah the Automapping is driving me nuts.

I've now got one user who could access the mailbox fine the other day but is now getting access errors.

I despair of Microsoft I really do - why does everything have to be so damned hard?

16-bit · 4 May 2017 at 10:25

Automapping also breaks if your not running at least Outlook 2010 SP2