Have you not searched the archives of this newsgroup? There are TONS of
posts about this.
The Garmin devices pretty much don't work.
> Has anyone tried to update a Garmin GPS via USB using VPC 7?
>
> I can not get VPC to recognize the Garmin device.
Very belated reply, but I've never had a problem updating the firmware
via VPC (6 or 7), using both a PowerBook G4 12" and a G5, both under
10.3 (haven't tried it under Tiger yet). I've done this with a 2620 and
a Vista C (also USB-only). I also installed the City Navigator 6 DVD
(updating from 5) onto the 2620 with no problem. I have never, however,
been able to get MapSource work with any Garmin GPS and VPC.
For those who don't know, MacGPS Pro 6 now works with USB-based Garmin
GPSs, native to OS X.

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