Symptom:

The Event Viewer shows the error message "Syntax error in configuration file for key preferredNameServers" and the DNS Expert AD Monitor service does not start.

Problem:

This can happen if the user chooses to use a specific DNS server for zone transfers, but fails to enter the IP address of the DNS server to use.  So the system can be left in an in-between state where the required key for the DNS servers to use is non-existent and this causes the service to fail to start with the error stated in the event log.

Solution

To fix this, the user must enter the IP address of the DNS server to use:
  1. Start the DNS Expert AD Monitor program
  2. Choose Tools -> Options
  3. Choose the Advanced Options tab
  4. Click the Specify Servers button. This will display a dialog box containing a tree where the root note is 'Preferred DNS Servers' and each subnode is a domain. Each domain in this tree must have one or more subnodes where each node is the IP address of a DNS server to use for zone transfers.
  5. Select each domain that does not have a DNS server specified and click the 'Add IP Address' button
  6. Enter the IP address of the DNS server to use for zone transfers for the domain. This DNS Server must be configured to allow DNS Zonetransfer (AXFR over Port 53/TCP).