Shudown and HORM

Normal XPe shutdown, even when using HORM, takes about 20 seconds on our system.

What is the OS doing? The C: drive is write-protected, so it can't be saving anything.

We do have an un-write-protected USB thumb drive,but that should not take long to flush out.

Is there some way to speed this up? Note that we are using an ATX power supply: The user pushes the powerw off button. This is intercepted by our application which closes down (including closing the file on the USB thumb drive), then signals the OS to proceed to shut down. Our application takes only a second or two to shut down. Most of the 20 second shutdown is spent with the Windows shutdown screen.
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