I am running XP SP3 and logging into a Windows Vista machine using RDP 6.1 (also tried 7.0) with NLA. I've done the registry configuration enabling SSO (although reproduced this without those registry entries using fresh credentials). The first logon works perfectly. I log off the Vista machine. Then, the second login comes up with "An authentication error occurred (0xc00002fd)." I can never get another login to work. I reboot XP and it will work again, once. The error appears to be some kind of encryption issue. Could it be that CredSSP is caching something that does not work? Any help greatly appreciated!

Hi Brandli, Is the Windows Vista computer on a domain network? This error can sometimes occur if Credential Security Support Provider (CredSSP) is not properly enabled. You may access the link below and follow the steps in the article to turn on CredSSP.http://support.microsoft.com/kb/951608/en-us?p=1If the issue persists after following the steps in the above article, you may access the link below and post your issue in theTechNet community, that will offer the support you request.http://social.technet.microsoft.com/Forums/en/virtualmachinemanager/threads Hope this helps. Let us know the result. Thanks and Regards, Srinivas RMicrosoft Support.Visit our Microsoft Answers Feedback Forum and let us know what you think.

Hello,Did you ever find a resolution to this issue? We are experiencing exactly the same behavior only with Windows 7 instead of Vista. This, coupled with the fact that we are for some reason unable to turn off NLA on our Windows 7 boxes permanently has seriously impacted our ability to deploy Windows 7 (there appears to be a domain group policy that affects this but apparently none of the network admins can figure out where or how it is being applied). Turning off NLA resolves the 'one login per reboot' issue for us but is not currently a permanent solution because eventually the mysterious group policy thing turns NLA back on again.