I've scheduled C:\WINNT\System32\dfrg.msc to run at 01:07 every night... except that it doesn't run, it just sits there, waiting for me to click something.

Is there a way to tell it which disk to defragment, from the command line? Or is this one of Microsoft's "everything will have to be clicked at, what do you want, automation? No way, that's for computers!".