The card reader is the simplest solution.
I have a number of digital cameras and none have ever been connected to my computer.
That way, I never have to load any of the software that came with the camera(s).
You could have a bad USB cable (try another one)
You could have a bad USB port on the computer (try another one).
You could have a bad USB interface in the camera itself.
It could be the software you are using.
My G6 won't send photos to my computer after I left it connected to one of my computers overnight. Camera won't even come on when I plug it in to USB. 'My Computer' won't recognize the camera even when I turn it on. I can see all my photos on the camera LCD monitor, so its not a bad flash card.
Has anyone out there in DC land ever experienced this?
Is my only solution a card reader?