Hi Kevin,
Windows server not original have this option to customize this message, based on my experience you can customize the Winlogon Credential Providers to realize that, since this
is more related about develop code I suggest you ask in MSDN forum.
The related information:
Winlogon and Credential Providers
http://msdn.microsoft.com/en-us/library/windows/desktop/bb648647(v=vs.85).aspx
MSDN forum Developer Network
http://social.msdn.microsoft.com/Forums/en-US/home?forum=WAVirtualMachinesVirtualNetwork&filter=alltypes&sort=lastpostdesc
Thanks for your understanding and support.
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