Hi If you have recently implemented MFA ( Enforced mode in your tennant). I have found that there is no much information about the Dirsync Account status. As per now if you do enforce mfa the account will be affected. Hence breaking the sync as shown In order to resolve: You will have to exception … Continue reading Event 659 – Error while retrieving password policy sync configuration. System.InvalidOperationException: The ADSync service is not allowed to interact with the desktop to authenticate This error may occur if multifactor or other interactive authentication policies are accidentally enabled for the synchronization account.