Here is the deal...I'm doing a hybrid migration from an acquired company (Exchange 2010 on prem) into an existing O365 tenant using minimal hybrid. Because the acquired company's AD doesn't sync with the tenant I'm just copying over the ExchangeGuids to the parent company's AD and the migration works great. None of this is the problem.
Here is the problem...prior to having their mailboxes go live I must provision archives in the cloud for these users because we are going to pre-populate them with their archive data that is coming from another system.
I can't seem to get O365 to create the remote archives without the primary mailboxes being in the cloud. If I give the user an E5 license and then go to Exchange 2010 and tell it to enable a remote archive it says it is doing it and sets a bunch of attributes in the local AD like the MSExchArchiveGuid and the msExchRemoteRecipientType=2 and the MSExchArchiveName but then I assume because that AD doesn't sync with O365 nothing happens that is somewhat expected. On the other hand I populated those three attributes in the AD that DOES sync with O365 and still nothing happens. Am I missing an attribute or do I just not understand how this is supposed to work (pretty sure that is true) or is this even possible