The way I have mine setup, the external USB drive I have gets "scanned" by MCE evertime it resumes.

I've changed the settings in the drvie properties to "do nothing" on each of the files types, but this doesn't seem to change the way that MCE treats the drive.

Any clues?

Funnily enough, I've just managed to do it:

http://www.howtogeek.com/howto/windows/disable-autoplay-of-audio-cds-and-usb-drives/

But this only gives me the option for "all drives"

I might try this:

http://thegreenbutton.com/forums/thread/227479.aspx