I have been getting this error message but only when I click on the Backup button in DriveImage XML an open-source imaging program. I tried the applicable suggestions on the forum thus far and none worked in my situation (including uninstalling QuickTime).
The following, however, 'worked' for me. I put a disk in my zip drive before opening DriveImage XML and the message went away.
The drive image software obviously performs a quick scan across the drives to load information about each drive in the selection window and was reporting not seeing a disk in the zip drive.
I thought I would post this observation because, while it may not identify the underlying issue of what changed on all these boxes to cause the problem, it does seem clear why different users are reporting seeing this error thrown when running different pieces of software: each piece of software/process is probably running a disk identification routine.
Hope this helps someone.