USB Mass Storage Example MSC USBMEM on Win7 x64

Good day to all
(and Tsuneo ;))

My MCB2300 USBMEM sample works well on all tested 32 bit Win versions including 7.
But on Win7 x64 it does not.

Device manager lists a mass storage that is said to be working well, but no drive shows up in explorer. Are there any new limitations in x64, eg regarding minimum drive size?

Any hints highly appreciated.
Uli

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