Windows Vista - http://www.vistaarticles.com
Cannot use Tablet PC Input Panel
http://www.vistaarticles.com/articles/225/1/Cannot-use-Tablet-PC-Input-Panel
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Published on 12/10/2006
 
The Tablet PC Input Panel is unavailable.

Cannot use Tablet PC Input Panel

To work around this problem, use a standard keyboard to enter administrator credentials.

This problem occurs because the Tablet PC Input Panel always runs in the security context of a standard user account. To block malicious software from acquiring elevated administrator rights and permissions, Windows Vista only lets trusted processes run when you try to start an application that requires administrator credentials. Trusted processes are processes that run in the security context of an administrator account.