In my past article for multi geo, I explained how to use extensionAttribute1 to populate preferredDataLocation  attribute on office 365 mailboxes for users synchronized through azure ad connect. Microsoft says couple of times about extensionAttribute1 hence most of us may just focus on this article and think that if extensionAttribute ranging from 1 to 14  are exhausted … Continue reading Update preferredDataLocation value for Multi-Geo using a non extensionAttribute