Internal Apple USB Reader Error

[pbscnl21]

Schermata 2014-01-13 alle 17.47.46.jpg (93.33 KiB) Viewed 958 times

Sorry for my poor english, this is what happen:
I'm running Window 7 Guest under OSX Maverick 10.9.1, Mack Book Air with SSD 512 and 8 Gb Ram
VB 4.3.6 r41906, last extension pack and guest addiction installed, USB Config checked.
No way to see the internal USB reader even without Memory (SDHC 32 Gb / Sandisk) inserted.
Any idea or solution ?!?!
i've attached the screenshot of the error.

[socratis]

Most probably, the host OS is capturing the card-reader at boot time exclusively for its own use. There was a similar topic about the internal Bluetooth recently. Although capturing the card-reader maybe tricky, I would try to capture the SSD card that you insert into it (via Shared Folders). It should show up as an external HD, no? I don't have the hardware to verify it...