Why won't my External HDD's show up?

I recently updated to Snow Leopard, and now am at 10.6.3 from Tiger 10.4.11.

I took a SuperDuper Backup of user files before updating to SL, and now want to use a different external to set up Time Machine, but no external HDD's or removable devices are showing up

Any idea's?

Ta
Alex

Make sure you have selected "show hard drives on the desktop" in the Finder preferences.

Regards.

I ticked the HDD box, but the external box was already ticked
One HDD will show up now, the one I backed up with Superduper.
But the other that is still formated for Mac OS X (Journal) isn't showing.
Any idea's?

Thanks

ALL SORTED.
Just formatted it on my PC again, plugged it in, and away I go
Sorry for being a constant retard on this forum, and wasting everyone's valuable time.

Ta
Alex

You're not wasting our time. And as far as asking questions, even basic ones, how else can you learn? Glad we could help.

Regards.