Exchange Online Optimizes Online Address Book Lookups
Microsoft is changing the way that Exchange Online address book updates work to force users to use search rather than browsing through the GAL/OAB. That’s fine and should improve things. When playing with finding how many items are in the GAL, I found that the Get-MgDomainNameReference cmdlet appears to have some issues. First, it can only return up to 999 items, which isn’t a lot when you’re dealing with users and groups that have a connection to a domain. Second, it doesn’t return a nextlink, so you can never fetch all available items. It just goes to prove that Microsoft Graph PowerShell SDK cmdlets are at the mercy of the underlying APIs.