The AD Op Master Response Monitor failed consecutive attempts to bind or ping the primary domain controller (PDC) emulator operations master (also known as the PDC flexible single master operations (FSMO) role holder).
This is more than a transient error, and it should be investigated. The PDC must be available at all times. If the domain controller that holds this role is unavailable, consider transferring the role to another domain controller.
To view all the events that are generated by the AD Op Master Response Monitor, open the AD MP Events view. These events provide more detailed information about the errors that occur during testing of the operations masters.