Description of problem:

Customer cannot do SSO after enabling secure logon (Ctrl+Alt+Delete). 
When secure logon is disabled login using SSO works properly. 
http://windows.microsoft.com/en-us/windows/enable-disable-ctrl-alt-delete-logon 

The agent logs (C:\ProgramFiles\RedHat\RHEV\Tools\InstallLogs\Install.rhev-agent-service) on Windows I see: 

Trying to login with SecureLogin (Ctrl + Alt + Del): 
Dummy-1::INFO::2014-07-11 22:59:45,596::ovirtguestservice::63::root::Starting OVirt Guest Agent service
Dummy-2::INFO::2014-07-12 00:05:33,802::ovirtagentlogic::266::root::Received an external command: lock-screen...
Dummy-2::ERROR::2014-07-12 00:05:33,802::guestagentwin32::302::root::LockWorkStation exception
Traceback (most recent call last):
  File "GuestAgentWin32.pyc", line 272, in LockWorkStation                               <<<-----------------===============-----------------
error: (1008, 'WTSQueryUserToken', 'Wykonano pr\xf3b\xea odwo\xb3ania si\xea do tokena, kt\xf3ry nie istnieje.')
Dummy-2::INFO::2014-07-12 00:05:33,990::ovirtagentlogic::266::root::Received an external command: login...
Dummy-2::ERROR::2014-07-12 00:05:35,006::guestagentwin32::197::root::Error writing credentials to pipe [1/3] (error = 2)
Dummy-2::ERROR::2014-07-12 00:05:36,006::guestagentwin32::197::root::Error writing credentials to pipe [2/3] (error = 2)
Dummy-2::ERROR::2014-07-12 00:05:37,006::guestagentwin32::197::root::Error writing credentials to pipe [3/3] (error = 2)
Dummy-2::INFO::2014-07-12 00:07:07,911::ovirtagentlogic::266::root::Received an external command: lock-screen...
Dummy-2::ERROR::2014-07-12 00:07:07,911::guestagentwin32::302::root::LockWorkStation exception
Traceback (most recent call last):
  File "GuestAgentWin32.pyc", line 272, in LockWorkStation

After a manual press CTRL+ALT+DEL is ok: 
Dummy-2 :: INFO :: 2014-07-12 10:24:01,197 :: ovirtagentlogic :: 266 :: root :: Received an external command: login ... 

In version 3.3 (RHEV-toolsSetup_3.3_14.iso) this works fine . Issue noticed on RHEV-toolsSetup_3.4_7.iso .

I guess the code points to :
===============================================================
 263     # The LockWorkStation function is callable only by processes running on the
264     # interactive desktop.
265     def LockWorkStation(self):
266         try:
267             logging.debug("LockWorkStation was called.")
268             sessionId = GetActiveSessionId()
269             if sessionId != 0xffffffff:
270                 logging.debug("Locking workstation (session %d)", sessionId)
271                 dupToken = None
272                 userToken = win32ts.WTSQueryUserToken(sessionId)
273                 if userToken is not None:
274                     logging.debug("Got the active user token.")
275                     # The following access rights are required 
===============================================================

Similar bug for w2k12
https://bugzilla.redhat.com/show_bug.cgi?id=965664


Version-Release number of selected component (if applicable):
 3.4.0-0.22 
Win7-32bit
RHEV-toolsSetup_3.4_7.iso ( works well on RHEV-toolsSetup_3.3_14.iso )

How reproducible:
Always

Steps to Reproduce:
1.
2.
3.

Actual results:
SSO does not work after a control+alt+delete

Expected results:
SSo works while accessing guest console .

Additional info:
http://windows.microsoft.com/en-us/windows/enable-disable-ctrl-alt-delete-logon