I don't have Windows and can't reproduce this problem myself.
If someone is able to reproduce the problem, still able to install mods, and willing to do some potentially dangerous experiments... we could test if exposing the USB device in a different way [as a partition instead of full block device] might help (by changing /usr/local/Kobo/udev/usb script).
If there is a volunteer (preferably someone with access to the internal SD card, in case things go really south), send me a PM.
Edit: Oh sorry, I see this thread was about Windows 7, should probably have posted in the other one. (
https://www.mobileread.com/forums/sho...d.php?t=276349 )