Quick update with some more info on this error message. I have tracked the problem down to a USB card reader. The error does get thrown up whenever any USB storage device is attached, having seen this now with a USB external HDD (NTFS) and USB external floppy, but only when the card reader is present (and it is normally connected all of the time). It seems the drives that the SSD Toolbox is searching for and cannot find are the vacant card reader slots. When the card reader is removed I can use USB storage devices and launch Toolbox without any problems. Don't know if this is specific to this particular model of card reader, which is a Sandisk Imagemate All-in-One USB 2.0, or if this will occurr with all USB card readers in general?
Running it manually is the problem. Whenever the toolbox is launched with a USB storage drive attached it throws up an error and cycles through a drive not found error many times before allowing me to access the interface. Not a big deal but thought it was worthwhile sharing this issue here in case others have experienced this and been unable to trace the problem. Seems like the Toolbox is scanning for USB storage devices and under the circumstances given above, throws a hissy fit. Scheduled runs seem to be working as advertised, at least according to the event log.
For what it's worth, I'm encountering the same issue.
Daily automated runs of the SSD toolbox appear to be functioning as they should, best I can tell.
I simply went to check on things manually given all the issues some have had with the latest firmware (which haven't hit me, knock on wood).
Multiple errors on load of no disk in the drive that I didn't get before. My machine does have a built in card reader, and USB devices I periodically attach. After clicking cancel many times the toolbox finally loads and functions as normal. Never got this before when running it manually, but just occurred today that I noticed.