I've been having this error for while now, I connect to one of the servers and it starts doing its thing apparently going through every step just fine but then I get this Access is denied message:
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Normally I wouldn't bother trying to fix it because I don't have the time nor the resources to throw at it, I just snapshot the machine back to a working state, files will are centralized in non-Microsoft redundant servers, they are safe. However, when I
tried snapshotting back this VM way back to the beginning of the month the error was still there. I figured, it's a domain issue then, so I took it out of the domain and it still wouldn't let me in.
I connected to the machine's console (via Fusion, it's hosted on ESXi) and checked the log.
There was nothing descriptive except for a "reason code 12" which I knew meant basically nothing because I had looked for it before when this started happening, so I went deeper since my snapshot safety is over I need to know how's it fixed.
Most of the RDS related branches in the tree were empty but in Microsoft/Windows/RemoteDesktopServices-RdpCoreTS/Operational I found some data, actually a ton, 50+ events per connection attemp. They all occur in the same second. I started following the
messages, the one where everything fails is:
Disconnect trace:CUMRDPConnection Disconnect trace:'calling spGfxPlugin->PreDisconnect()' in CUMRDPConnection::PreDisconnect at 4477 err=[0xc], Error code:0xC
Here's a table of the logs I made copying them one by one, I tried adding it here but exceeded the message length: http://fetch.vitanetworks.link/stationary/technet/eventlogerror.pdf it's a PDF, so it should show right in the browser.
Using the system with another account reveals the user that failed to log in, tho whom access was denied, is somehowstill logged in. I was informed this when I tried to restart the computer and the warning I would kick other users out showed up. No configuration has been changed on the server, on DCs/GPOs, on the client, nor on the hypervisor. And of course I have
no idea what does that graphics thing mean.
The other directory with events was on Microsoft/Windows/RemoteDesktopServices-SessionServices/Operational with a way more decent 2 events per connection attempts:
1 Error The RDP display control module failed to change the session monitor layout. The operation failed with error code 0xFFFFFFFF.
2 Information The RDP display control module successfully changed the session monitor layout. New layout has 1 monitors.
And that's all the info I have. Could you point me where to go next to get more information or how to proceed from here? I don't want to reinstall Windows, I put way too much time on these machines. :/
Thanks for your help!
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