Recently, We have noticed that when an IP Address is allocated to a user via DHCP, it does not automatically create a DNS A Record... This isnt for every host, it appears to be intermittent.
So when programs that rely upon DNS for host to IP or visa versa... Communication is failing.
If i manually do: "ipconfig /release" and then "ipconfig /renew" on the machine in question, the A Record is then created and the problem is solved... However, this is only a manual fix and we would like to find the root cause as to why these A Records arent being made automatically.
Also, i have found some event log errors on the machines that do not create A Records automatically...
The eventlog error is: "the system failed to register host (a or aaaa) resource records (rrs) for network adapter"