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Hi
I am unable to grant shared mailbox access to users in another trusted forest. I've used the command "Add-MailboxPermission sharedmailboxalias -User "DomainA\UserA" -AccessRights FullAccess" but is getting the error "User or group wasn't found. Please make sure you've typed it correctly."
May I know if this is by design not to be able to grant access to users in another trusted forest?
Regards,
Chiew Sheng
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Hi Chiew,
The error indicates the user cannot be found in the forest.
May I ask how the detailed configuration of the trust between the two forests?
Is it a one-way trust with incoming or outgoing or a two-way trust?
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Hi Kael, thank you for your reply.
How do you create a cross-forest mail contact? I only see options for new "mail contact" and "mail user".
Hi,
Thanks for the update!
I retested it in my lab and have edited my former reply.
I suppose the cause may be with the trust settings between the forests.
Sorry for the confusion caused.
I am writing here to confirm with you how thing going now?
If you need further help, please provide more detailed information, so that we can give more appropriate suggestions.
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Hi the 2 forest have a 2 way forest trust. Can you provide a screenshot how it is done?
Hi,
Sure.
Scenario:
tailspintoys.com and contoso.com have a forest two-way trust.
Exchange is installed in domain contoso.com.
tailspintoys.com:
contoso.com:
User01 is a user in tailspintoys.com and share is a shared mailbox in contoso.com.
tailspintoys\User01:
contoso\share:
If the two way trust was established correctly, the command in your main post should work without problems.
Add-MailboxPermission:
Hi Kael,
Many thanks for capturing the screenshot. I managed to add it using exchange Powershell. I am unable to add cross forest users using Exchange admin center as it does not have to option to choose cross forest users. Can I check with you is that the expected behaviour?
regards,
Chiew Sheng
Hi Chiew,
You are welcome. Glad to help.
I am unable to add cross forest users using Exchange admin center as it does not have to option to choose cross forest users. Can I check with you is that the expected behaviour?
Did you mean you would like to create mailboxes for users in the other forest?
If it is the case, instead of regular user mailboxes, you may need to create linked mailbox for them.
EAC: Use the EAC to create a linked mailbox
EMS: Use the Exchange Management Shell to create a linked mailbox
I meant to grant cross forest users access to my shared mailbox but is unable to do so using Exchange admin center. Can only do so using exchange Powershell.
After adding the cross forest users to the shared mailbox, can your cross forest users access the shared mailbox? My shared mailbox has granted permission to cross forest user but is unable to add. Are your cross forest users able to access the shared mailbox?
Hi,
Sorry I misunderstood the question.
Thanks for the clarification.
I meant to grant cross forest users access to my shared mailbox but is unable to do so using Exchange admin center. Can only do so using exchange Powershell.
Yes. EAC would only list the users in the current forest.
From the screenshot, I suppose you have Exchange servers in both two forests.
Have you tried with the mailbox address shareonprem1@theironmanlab2?
Hi Kael,
Yes I have 2 separate Exchange in both forest. I have tried adding using userprincipalname but it is not working as well. Is your setup using account and resource forest?
Hi Kael, do you provide remote support? I can share my screen so it is easier to explain my issue.
Hi,
Sorry here we mainly focus on supporting via forum posts and cannot provide remote support.
I will set up a lab and do some research on this issue.
It may take some time.
Thanks for your understanding.
Hi Kael,
Do you have any update for the cross forest users to access the shared mailbox?
Hi Chiew.
My apologies for the late reply.
The general steps are introduced in this link: Exchange Server 2010 Cross Forest Delegation
In short, you may need to: