Name resolution for some external websites fails on a Windows Server 2012-based DNS server that uses Internet root hints.
An incorrect Canonical Name (CNAME) record is returned by the DNS server when it processes an answer that contains a Delegation Name (DNAME) record.
Assume that you use Name Authority Pointer (NAPTR) records in your environment to locate Session Initiation Protocol (SIP) services for telephones. However, because the Windows Server 2012-based DNS server compresses NAPTR records, telephones cannot locate SIP services.
Cause of issue 1
This issue occurs because the authoritative server for the website has both a start of authority (SOA) record and a CNAME record on the website. This prevents the DNS server from resolving domain names correctly.
To fix this issue, install MS15-127: Security updates for Microsoft Windows DNS to address remote code execution: December 8, 2015.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminology that Microsoft uses to describe software updates.