When restoring a backup with the Online Restore Wizard for the step Objects to Be Processed, in the Add | Browse option and selecting the check mark "Show advanced objects", the DNS Zone may not appear in the DomainDnsZones partition (DC=DomainDnsZones,DC=www,DC=mydomain,DC=com).
解决办法
For DNS zones stored with "Windows 2000 compatibility", such zones may be stored in domain naming context partition. For example, CN=MicrosoftDNS,CN=System,DC=www,DC=mydomain,DC=com.