Azure AD Connect Error stopped-deletion-threshold-exceeded

Azure AD Connect Error stopped-deletion-threshold-exceeded. Azure AD Connect suddenly stopped replicating changes to Azure AD, including new user creations. Synchronization Service Manager showsstopped-deletion-threshold-exceeded against an Export operation.

Solution

In Azure AD Connect, there is a feature enabled by default to prevent more than 500 deletes.

The feature is designed to protect a customer from accidental Azure AD Connect configuration changes and changes to the local Active Directory, that would affect many objects.

To temporarily disable this protection and allow the deletes to be processed, run the following PowerShell cmdlet:

Disable-ADSyncExportDeletionThreshold

Provide Azure AD Global Administrator credentials for the tenant when prompted.

When the threshold is disabled, force a full synchronization:

Start-ADSyncSyncCycle -PolicyType Initial

Monitor the results, and wait for the full synchronization cycle to complete.

Then re-enable the protection threshold:

Enable-ADSyncExportDeletionThreshold -DeletionThreshold 500