Forum Discussion
Exchange 2019 Cross forest mailbox delegation error
Hello, I am trying to give a user from a forest A fullaccess to a shared mailbox located in forest B. Bidirectional trust is configured on the forests. I use this command from Forest A: ...
Hi Arnaud_Roffe,
The error you're experiencing is linked to the msExchVersion attribute in Active Directory for cross-forest contacts. Specifically, the Add-MailboxPermission command requires a specific value for this attribute to function correctly.
A common workaround involves modifying the msExchVersion attribute from 88218628259840 (indicating Exchange 2013) to 1125899906842624 (representing Exchange 2016).
While this adjustment covers the successful execution of the Add-MailboxPermission command, it doesn't impact the functionality of the Add-MailboxFolderPermission command.
Microsoft does not officially support this approach.
You can consider alternative solutions such as migrating the shared mailbox to the same forest as the user, or syncing the Global Address List (GAL) between the two forests.
Yoou can use these links for more information:
Exchange 2019 cross-forest permission issue, msExchVersion strange behaviour. - Microsoft Q&A
Exchange Cross Forest Shared mailbox delegation (microsoft.com)
practical365.com
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Kindest regards,
Leon Pavesic
(LinkedIn)
- Hello,
We finally find a solution.
We have configured MIM to clear the msexchmasteraccountsid attribute on the contact.
After doing that, we are able to set the mailbox permissions without arror. And cross forest sharedmailbox access works as expected.
Arnaud
