When I issue an ACPI shutdown command to a Windows XP guest machine from the host VM server, I want Windows to shutdown.

The problem is, Windows always wants to ask some question or another, rather than just shutting down. I need shutdown to be reliable, no matter what is running or going on, so I can automate shutdowns from the host machine. But I want it to be as graceful as possible, rather than just pulling the plug.

Some problems:

• If a user is logged in, ACPI shutdown causes a box to appear that says, "are you sure you want to shutdown while other users are logged in"? And this prevents shutdown until someone connects to the machine and clicks "yes". In this case, it should try its best to gracefully log out all users, using force if necessary, and then shutdown without promoting.

• Busy or non-responding programs or programs asking to save data can prevent Windows from shutting down until a user answers a prompt. This should attempt to save data, wait maybe 30 seconds for non-responding programs, but should get aggressive with stubborn programs. "nope, time's up! 3,2,1, Goodbye!"

Is there a registry setting that I can change from:

ACPI_Shutdown: "Shut down if Windows feels like it"

to

ACPI_Shutdown: "Just do it. Kill programs, bump users, try to be graceful about it, but when I come back, I expect you to be off."

This should respond to the ACPI shutdown command, and not be a script on windows, unless that script is triggered by the ACPI power button. I'm hoping this can be changed with registry options.