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Microsoft Security Update Issue

Posted on 2016-09-30
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Last Modified: 2016-10-22
After installing August and September security patched the end users receive an error can not contact domain controller when users are attempting to change their password.

Domain controllers are running Windows Server 2008 R2 SP1,   clients are Windows 7, Windows 8.  

Is there a security patch needed on the domain controller to fix this issue?   Does anyone know steps to fix without uninstalling the security updates?
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Question by:Member_2_4576574
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btan earned 2000 total points (awarded by participants)
ID: 41823781
Looks like it may be this case as shared in the forum
Check that you have UDP/TCP 464 (kpasswd) open between your clients and your DC's....
he default Active Directory service group did not have it open -- We just recently made the move to Win 10 so I figure maybe that's why it used to work.  Looks like Win7 defaulted to kpasswd but would fall back to SAM.  I'm thinking Windows 10 is kpasswd only.
I figured this one out by looking at the DNS SRV records and noticed the _kpasswd entries "[0][100][464] DCNAME.DOMAINNAME" and spotted a few drops in my firewall.
https://social.technet.microsoft.com/Forums/windowsserver/en-US/40107f29-5da8-4341-893f-245fc0882f44/users-get-the-system-cannot-contact-a-domain-controller-to-service-the-authentication-request?forum=winservergen
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Author Comment

by:Member_2_4576574
ID: 41823792
This fixed the issue for us.  Thank you for the quick response.
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LVL 56

Expert Comment

by:McKnife
ID: 41824688
Out of interest, which particular step solved it? (and why would this be needed, updates don't modify firewall rules?)
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Author Comment

by:Member_2_4576574
ID: 41826848
Mcknife,  we opened up UDP/TCP 464 on our firewall.
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Expert Comment

by:btan
ID: 41855068
As per advice given.
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