This is a problem that started a couple months ago out of the blue. As far as we know we made no changes to DNS or DHCP.
Suddenly we started getting a lot of computers (I think when their DHCP leases expired) having problems getting DNS records created. They are able to get an IP assigned via DHCP, but no associated A or PTR records are being created. But only for SOME computers. My computer, for example, has not had this problem once, even when my lease expires and is renewed.
A couple other desktop computers in the building have had the same problem half a dozen times.
The way that we've been able to fix it varies, so I'm honestly not sure we're even doing anything or just getting lucky and eventually it starts working. We've tried everything from reboots, to network drivers, to restarting the DHCP/DNS servers to deleting the DHCP and DNS records manually, to assigning static IP addresses.
Nothing seems to work consistently. Sometimes a computer will just suddenly start working and I can never be sure which thing I did made it happen.
Manually assigning DNS records does not work.
When I run a DCDIAG on the server that does both DHCP and DNS (the primary server) it gives me a warning about not having credentials set up for Dynamic DNS updates. However, this has not been a problem until very recently. We've always had some strange DNS quirks, but usually related to there being multiple DNS A records for a single IP address but with different names.
Right now it seems like any new record that's been created in the last few months is not updating correctly, but older ones are fine. Almost all of the computers I'm having problems with are newer windows 7 computers installed within the last 5-6 months. Every once in a while we have a problem with an XP computer, always a laptop that hasn't seen much use and probably hadn't had a DNS or DHCP record for a while.