Check this MS guide - https://learn.microsoft.com/en-us/exchange/troubleshoot/administration/validation-errors-for-mailbox-archive-guid
User migration with 365 mailboxes/archive
Hello All,
Both AD environments are in Hybrid mode. They have their mailboxes in 365 along with their Archive mailboxes, in Domain A and B. AADC exits in the Target Domain, which syncs user from A&B into 365
I am migrating Users from Domain A > Domain B. . Users get migrated from A > B no problem, the users reattach to their Mailboxes/Archive mailboxes no problem in 365. When in Domain B
The Users mailbox in Domain A before and after shows as a remote User. After the user is migrated to B, he does not show up in Exchange at all, which is normal. They can open their mailbox and archive mail box and see the data within without issue. When I go into 365 and look at the properties of the users Archive I find the following error message:
"Failed to enable the new cloud archive <ArchiveGUID> of mailbox <MailboxGUID> because a different archive<ArchiveGUID>exists. To enable the new archive, first disable the archive on-premises. After the next DirSync sync cycle, enable the archive on-premises again."
I'm assuming that I must convert the user in Domain B to a Remote user? Then they will show up in the Domain B Exchange environment? Then reconnect their Archive to them with the Cloud GUID? Am I correct?
Thanks,