Hello Administrator,
This is an auto-generated email to notify you that Active Directory Synchronization encountered 1 failure(s) while it was processing some User(s) from your company. Following is the list of failed User(s):
user1@democloud.com
user2@democloud.com
Please try to run the synchronization process again. If the problem persists, please contact your client services representative.
1. The mailbox which the sync tools are trying to sync, the archive for that mailbox was made non-discoverable by soft deleting it using Account Management in the Admin Console.
2. The mailbox which the sync tools are trying to sync, is listed as an inactive alias on an archive.
This can be verified by looking up the users you got the error for in Account Management in Manage Console. If they don't show up in the results, one of the above causes applies.

Please contact support to reactivate the soft-deleted (deactivated) archives/aliases to resolve the issue.
Active Directory Synchronization Failure alert is triggered when Office 365 Sync & Cloudlink attempts to scan an archive/alias which is currently in soft deleted (deactivated) state.