When running NSLOOKUP against dc dns you might get error and the dns stop resolving records, local and internet. When running dcdiag /test:dns you might get errors like this:
Running enterprise tests on : domain.com Starting test: DNS Test results for domain controllers: DC: SERVER.Domain.com Domain: Domain.com TEST: Basic (Basc) Error: Can't read OS version through WMI No host records (A or AAAA) were found for this DC Summary of DNS test results: Auth Basc Forw Del Dyn RReg Ext _________________________________________________________________ Domain: Domain.com SERVER PASS FAIL n/a n/a n/a n/a n/a ......................... domain.com failed test DNS
To fix the DNS functionality try this steps, first try to rest the DNS cache:
net stop netlogon net stop dns DNSCMD ServerName /clearcache After that, please rename the following two files located in the Windows\System32\Config: 1) netlogon.dmb to netlogon.dmb.old 2) netlogon.dns to netlogon.dns.old Then, please run the following commands: net start netlogon net start dns ipconfig /registerdns
Test the dns with nslookup :
from the CMD run nslookup "Your DC Name" or nslookup google.com
If that didn’t work try reseting the WMI repository, First run:
winmgmt /verifyrepository
If the repository is in a consistent state I would recommend to stop and look for another solution how ever to reset the repository you can try :
Winmgmt /salvagerepository
That will take the content of the inconsistent repository and merge it into the rebuilt repository if it is readable, If this failed the try :
Winmgmt /resetrepository
*. I have seen cases thet the WMI service can not be stopped, pausing the service will help as well 
That will reset repository to the initial state when the OS was first installed . More information about resetting the WMI can be found here
Then reboot the server !