The cause of the problem is that after you install UAG SP1, the DNS64 service is set to Manual. You need to reconfigure the DNS64 service to start automatically. This issue is documented in the UAG SP1 Release Notes at http://technet.microsoft.com/en-us/library/gg315322.aspx
After installing SP1 RTM on a Forefront UAG server running SP1 RC and acting as a DirectAccess server, the DNS64 service will be set to Manual. Following the installation, set the DNS64 service to Automatic and start the service.
BTW – if you were trying to troubleshoot this issue, you would have been exposed to this scenario in the Test Lab Guide: Troubleshoot UAG DirectAccess which you can find http://www.microsoft.com/downloads/en/details.aspx?displaylang=en&FamilyID=d2e460c8-b4bf-4fda-9f86-ecc4b7add5d1 (just thought you’d like to know - there’s a lot of other cool troubleshooting scenarios and information in that Test Lab Guide, so give it a try when you have a chance).
Microsoft ISD iX/SCD iX
UAG Direct Access/Anywhere Access Group (AAG)
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