Thin Clients based on Linux and NT can not logon to Win2012 Terminal Server

I have installed a Windows 2012 Terminal Server replacing our old 2003 Server
I can logon to Remote Desktop from our XP, WIndows 7 and Windows 8 Computer,but with the introduction of 2012 I can not logon with our thin clients
We have 2 versions
NEXterminal with eLux NG
ee400 TC NT Based thin clients

Before I installed Terminal Server Host on the server, the thin clients could access Remote Desktop Session but this only allow 2 simultaniously connections.
I then installed the Terminal Server Host on the server and ever since that, the thin clients can not gain access
I cant update the clients, however I know a case from last year with a simular situation with a Win2008 and resolved without updating clients.
See attached message from the NT Clients.

Any idea?
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The default for Windows 2012 is probably to use Network Level Authentication (NLA).  Basically, it verifies that the client can authenticate before it allows the connection.  In Windows 2008 R2, there was an easy option to disable this.  And it is probably the same case in 2012.


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Spike99On-Site IT TechnicianCommented:
Which version of RDP is embedded in those thin client OSs?

According to a blog post I found, If it's RDP 5, you might be out of luck.  Only RDP 6.x & later is supported with Server 2012.  Users can connect using RDP 5.x only if is there is no license server.  If you have an RDS license server, then you will have to upgrade to newer thin clients that have RDP 6 or later.

See this blog post written by someone who had a similar issue, although the error he got was different from the one your users are seeing:
morten444Author Commented:
Thanks for your reply. Sorry was on holidays so therefore late reply.
I check out the Network Level Autentication as soon as I have got the Terminal Sever up and running

REgarding the Compatibility....
RDP version 6.. hm i see. We had the same problem with Windows 2008 but someone found a solution for it, so there must be a work around somewhere

I will come back to this thread later today as opening another thread for RDS installation first
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Windows Server 2012

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