LDAP Responding on TCP but not UDP - Win 2008

[Viensterrr]

I am using Windows 2008 Domain Controller. I am also using portqry to test ?LDAP connectivity that it responds to TCP but not UDP, check below for instance:

C:\PortQryV2>portqry -n dc1 -p udp -e 389
Querying target system called:
dc1
Attempting to resolve name to IP address...

Name resolved to 10.0.0.17
querying...
UDP port 389 (unknown service): LISTENING or FILTERED
Using ephemeral source port
Sending LDAP query to UDP port 389...
LDAP query to port 389 failed
Server did not respond to LDAP query

There is only a switch between me and the DC and there are no firewalls or hardware or software. Can anyone tell me how to solve this problem. Thanks.

[Zachary]

You can try to run diagnostics against your Active Directory Domain. Incase you do not have the support tools installed on the machine, then install those from your server disk. After that try to run dcdiag, netdiag and repadmin in verbose mode.

• DCDIAG /V /C /D /E /s:yourdcname > c:\dcdiag.log
• netdiag.exe /v > c:\netdiag.log (On each dc)
• dnslint /ad /s "ip address of your dc"

[spencerm]

I get the same error on all of the 2008 domain controllers I have tested. If you restarted ADDS and retest UDP 389 will respond back. I have goofed around with uninstalling updated/turning off windows firewall/etd and no luck. I enabled auditpol to grab extra logging and enabled NTDS logging but haven't come across anything that helps.