Unfortunately, he ended up buying a new computer.
Since I have both revisions installed, I will try to find the fix.
Interesting, but confirms that it was something odd and very unusual on the computer he was using at that time... and that computer was from a different manufacturer than yours.
UPMan did mention that the part of the Sentinel program code that looks for removable drives and excludes other drives from that "clear user data - display all drives" box was put into BCDx36HP Sentinel version 1.07.05 as a safeguard so that users couldn't confuse their primary hard drive for the SD card.
That version was released over a year ago, and Sentinel for the HP1&2 has used that same code since 2009.
With all the copies of those 2 Sentinel versions that are out there, all the different users that own either the HP1&2, 436HP, and the 536HP, and all the widely varied configurations of computers that have been used for those applications over that span of time.... It would probably be a very difficult task to find the specific problem that has affected only 2 computers given the scope of those circumstances.
Some other thoughts (that may have been covered in that other thread)....
Is your card reader connected to your computer by a USB cable? If so, and when you connect your scanner to the computer with the USB cable, are they connected directly to the computer or do they go through a hub?
Also, if your scanner (or card reader) is connected to a USB3 port, does that same computer have a USB2 port you can try?
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