XenDesktop - Error "Cannot start desktop W2k8Test1" - No available resource found for user

I´m installing first XenDesktop 7 Infrastructure for productive use at customer site
and stucked at following problem:

Win2008R2 Worker in XenDesktop 7 Site (DC Windows Server 2008 R2) deployed mit MCS
When i try to connect session from Storefront i´m getting the following error on Storefront Website

"Cannot start desktop W2k8Test1"


and the following eventlog error on Storefront server:

Event ID: 0, Citrix Store service
No available resource found for user domain\user when accessing desktop group Desktop Group.

CDF Trace didnt give me any mor information.

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1006 0 (07/22/2013) 10:24:54:227 5040 1188 #dotNet# ****** ****** ****** ****** ****** BrokerDAL:8:5:DAL <<&lt; ResolveWorkerForLaunch(LaunchToken=fe8990cf-6f9e-xxxx-970b-675ebdfxxxxx): returns LaunchDataNoDesktopAvailable,W2k8TestB1,,,,Retry=,Restartable=False
 
1007 0 (07/22/2013) 10:24:54:230 5040 1188 #dotNet# ****** ****** ****** ****** ****** BrokerComponent:2:1:PrepareSession(): Launch failed: NoDesktopAvailable
 
1008 0 (07/22/2013) 10:24:54:230 5040 1188 #dotNet# ****** ****** ****** ****** ****** BrokerOpEvent:2:1:2013-07-22T08:24:54.2300000Z:ResourceLaunchFailure(W2k8TestB1 $S1-1, Group=xxxxxxx-c617-4d8f-xxxx-c79f13ecd629, Worker=, Session=, Client=172.16.X.X, Via=172.16.Y.Y, 70ms, User=S-1-5-21-xxxxxxx-4256275101-3180360253-500, domain\Admin, Admin@domain.intern, Admin, Reason=NoDesktopAvailable)
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But Get-BrokerMachine stated:

WindowsConnectionSetting : LogonDisabled

That pushed me in the right direction. Found the following Thread in Citrix Forum that said that VDA uses 4 Window RegKeyto define if RDS Connections are allowed or not.

One of the keys is
HKLM\SYSTEM\CurrentControlSet\Control\Terminal Server\fDenyTSConnections

and this one was set to 1.

That dont have any impact on RDS Connections,they works like a charme, but causes that XenDesktop could not establish a connection to that worker.

Set RegKey fDenyTSConnection to 0 resolved the problem.