External Hard Drive thru USB card

I was trying to run my external hard drive thru a USB 2.0 Notebook card. The card works with my printer, camera, etc. but won't read the hard drive. I powered the card (even though my hard drive is powered) and it still won't work.

any thoughts?

 

update: I think my problem is worse. The USB 2.0 notebook card works fine on another laptop (it recognizes the hard drive) so it must be a driver problem in my laptop. But I don't understand why the printer and camera will work thru the notebook card but not the external hard drive. Help?:confused

 

You say the drive and card work together on a different PC... does this PC have the same operating system, updates, and service pack(s) that your PC has? I'm assuming your PC has no 'built-in' USB ports if you need to use a card. Check with Windows Update and look in the optional hardware updates and see if an updated USB driver is available. If so, get it.... anyway, check your PC's software against the other PC and note any differences and post 'em if you need more help...