In support, we hear from people in this “duplicate mailbox” situation relatively often. When this happens, our customers ask us for the best way to recover. In my experience, there are typically two ...
Published Sep 11, 2019
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Blog Post
bwinzenz Thanks for responding and for the answer confirming that the successful / full count of copied messages is an indicator of success, at least in terms of what we're after here.
I do think that if that is how it is supposed to work, then the linked instructions should say so. Otherwise, how would anyone not in the product engineering group know that this failure is nothing to worry about? You must agree that not having this info as an outsider (me) substantially impacts my interpretation of whether or not I've succeeded with the process.
Regarding the next point, I agree that it's simple to understand how this stuff is working and how to avoid the issue. So you're concluding that it is easy to not pre-license too early. Well I'm concluding that it is extremely easy to pre-license too early, and so much so that it is highly likely to happen to most customers. If customers create a new AD user (no Exchange tools involved), sync it to AAD, and then it gets licensed before they've touched the on-premises object with an Exchange tool, boom it's got an orphaned mailbox in EXO, as far as Exchange on-premises is concerned. So yes your point is true that it is simple to avoid, but it's not obvious or advertised as a warning anywhere and every single customer has to go through this learning experience the hard way.
In summary, both your points are putting all onus on customers to just figure things out because they're 'simple' according to the Exchange product group. Meanwhile, I think I've raise perfectly reasonable points that state the opposite. Finally, to further strengthen my argument, particular to point #1 about the New-MailboxRestoreRequest failing and it still actually being a success, it seems a long way to go to create this blog post, only to not mention this crucial twist (that the job will fail, and that this is OK). Not sure where to go from here, so I'll just say thanks for confirming about this, and hopefully something changes for the better about this process.