Here's something I discovered this morning when working with a relative's machine.
If your machine likes displaying the error message "There is no disk in the drive. Please insert a disk into drive X:" (maybe with the title qttask) whenever you log in or you start Quick Time, here's one possible reason.
In QuickTime, you can save certain movies you have been played previously as favourites. The application also automatically saves a list of the latest files you've viewed. These lists are stored in a file called QuickTimeFavorites.qtr, and contains full path to the movie files. It seems like QuickTime for some reason tries to open each the movie files whenever you start the application - maybe to see if they still exist. If this list contains a file that's on a removable drive (e.g. a CD) or on a device that doesn't exist any more (maybe you repartitioned), the error message above pops up.
To work around this, you can make sure that the device can be read by QuickTime - e.g. always keep a CD, any CD, in the drive.
Or, to fix this problem, you can delete the file QuickTimeFavorites.qtr in your "C:\Documents and Settings\All Users\Application Data\QuickTime" directory and restart QuickTime. Note that this will make you lose your list of favorite and recently viewed movies. But at least the application will work again.
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