Vizio VTAB not seen by Calibre

Hi there,

When I connect my Vizio VTB to my laptop running XP it is seen by the OS as a Mobile Device. It appears in Windows Explorer not as a drive letter, but by name - i.e. it shows :

My Computer
..+ Local Drive C:
..+ Local Drive D:
..+ DVD Drive E:
..+ VTAB 1008
.... + Internal Storage
.... + SD Card
(Periods added to show indenting)

Calibre, however, does not see it at all. The debug data is:

[QUOTE]
Version: 0.8.61
USB devices on system:
[u'usb\\root_hub&vid1002&pid4389&rev0000',
u'usb\\root_hub&vid1002&pid4388&rev0000',
u'usb\\root_hub&vid1002&pid4387&rev0000',
u'usb\\root_hub&vid1002&pid438a&rev0000',
u'usb\\root_hub&vid1002&pid438b&rev0000',
u'usb\\root_hub20&vid1002&pid4386&rev0000',
u'usb\\vid_0489&pid_e040&rev_0227']
Traceback (most recent call last):
File "site-packages\calibre\devices\scanner.py", line 88, in __call__
DriveError: No removable drives found
Drives detected:
Available plugins: ADAM ALEX ALURATEK_COLOR ANDROID ARCHOS7O AVANT AZBOOKA BAMBOOK
BLACKBERRY BOEYE_BDX BOEYE_BEX BOOQ BOOX COBY COOL_ER CYBOOK DBOOK E52
E71X EB511 EB600 EBK52 ECLICTO EDGE EEEREADER ELONEX ESLICK EX124G
FOLDER_DEVICE_FOR_CONFIG GEMEI GER2 HANLINV3 HANLINV5 ILIAD INVESBOOK
IPAPYRUS IREXDR1000 IREXDR800 IRIVER_STORY ITALICA ITUNES JETBOOK
JETBOOK_COLOR JETBOOK_MINI KINDLE KINDLE2 KINDLE_DX KINDLE_FIRE KOBO
LIBREAIR LUMIREAD MENTOR MIBUK MOOVYBOOK N516 N770 N810 NEWSMY
NEXTBOOK NOOK NOOK_COLOR NUUT2 ODYSSEY ORIZON PALMPRE PDNOVEL
PDNOVEL_KOBO PI2 PICO PLAYBOOK POCKETBOOK301 POCKETBOOK360
POCKETBOOK360P POCKETBOOK602 POCKETBOOK622 POCKETBOOK701 PRS505 PRST1
README S60 SHINEBOOK SNE SOVOS SPECTRA STASH SUNSTECH_EB700 SWEEX
TECLAST_K3 THEBOOK TREKSTOR USER_DEFINED VELOCITYMICRO WEBOS WEXLER

Looking for devices...

Devices possibly connected: None
[UNQUOTE]

Any advice, please?

Richard