To troubleshoot synchronization issues with Azure Active Directory, it is important to understand the process and its troubleshooting steps. The following is a list of principles and steps to help you troubleshoot synchronization issues:

1. Ensure that all required Azure AD Connect components are running and healthy.
2. Learn the basics of, and the roles supported by, Azure AD Connect.
3. Check that your firewall isn't blocking required ports for the synchronization process.
4. Validate your user domains in the Azure portal and local Active Directory.
5. Check server time, time zone, and Daylight Saving Time settings.
6. Verify that there are no synchronization errors.
7. Verify that no conflicts exist in the synchronized user data.
8. Understand the synchronization process and its operations.
9. If you run objects through a sync rule, ensure the sync rule is configured correctly.
10. Check if synchronization is being handled via a partition container.
11. Verify that all necessary objects have been successfully synchronized.