Microsoft Entra Connect Sync Errors: Fixing Duplicate ProxyAddresses & ImmutableID Mismatches
When directory synchronization fails between on-premises Active Directory and Microsoft Entra ID (Azure AD), user provisioning grinds to a halt. Passwords stop syncing, newly hired employees cannot access their cloud mailboxes or Microsoft Teams, and administrators are flooded with automated emails: “Synchronization Error: AttributeValueMustBeUnique” or “Identity synchronization error report”. The vast majority of Entra Connect…
