[milhaus]

Toast 4.1 doesn't recognize the drive. Lacie Canada Help said "Basically, you're screwed. Check with Adaptec." Is there something I'm missing?
I've got a 4x2x8 USB drive: Toast 3.8 worked fine.

[Zwilnik]

Have you removed all the bits installed by Toast 3.8 first (extensions, Toast patches etc.) before installing 4.1 ? These can clash horrendously.
Also, check Adaptec's site for the compatability list of 4.1.
Generally, if it worked with 3.8, it should work with 4.1 (although I still prefer to use Toast 3.8 USB for my Freecom Traveller drive on its USB lead, while using 4.1 for when I'm using its Firewire lead).