This tip is for Windows Vista, 7, 2008 and 2008 R2.
Windows Vista introduced session 0 driver and service isolation. To understand why this is cool, see the following article; http://msdn.microsoft.com/en-us/windows/hardware/gg463353.aspx.
When a program running in session 0 displays a window an icon shows up in the taskbar that looks like the one in red.
Clicking on this icon shows a very interesting looking message that notifies you that a program is trying to display a message to you and if you would like to view it or have Windows ask later.
Selecting “View the message” will take you to the hidden session 0 desktop. Where you can view the window that the service or driver has displayed.
To create your very own session 0 message window you can use Sysinternals tool, PSEXEC to run Notepad.exe in session 0. Download PSEXEC and run from an elevated Command Prompt, by right-clicking the Command Prompt in Start->All Programs->Accessories->Command Prompt and selecting 'Run as administrator'.
psexec -i 0 -d notepad.exe
If anyone is out there and reading this, you may have noticed the scarcity of tips lately. Expect some new content in the future as I have moved on to a new position, Premier Field Engineer. I will be focusing on Platform Performance, so expect some good stuff on Windows, Performance and Reliability Monitor, hangs, memory dump analysis, Sysinternal tools, PowerShell and much, much more!
In the meantime check out some of my favorite blogs:
Mark Russinovich - http://blogs.technet.com/markrussinovich/default.aspx
Tess Ferrandez - http://blogs.msdn.com/tess/default.aspx
Raymond Chen - http://blogs.msdn.com/b/oldnewthing/
-Chad