Why won't my computer recognize both of my new external hard drives?

[blimkie.k]

I recently bought 2 - 1 tb external hard drives from tiger direct.

http://www.newegg.com/Product/Product.aspx?Item=N82E16822111019

My computer and other computers I have tried them on will not recognize them both plugged in together. it only recognizes the one i plug in first then when i plug the other one in nothing happens. When i unplug them both then plug in the other one it recognizes that one but not the second one. This is really frustrating. I couldn't find any related issues on google so i figured id see if anyone here has any ideas why I'm having this issue.

Thanks.

 

[Equate]

Maybe you need a driver? Just a thought, that's what I would be looking into...

 

[junglebeast]

Hmm, that's quite a strange issue for a USB drive.

This drive does not appear to have a special driver -- and I wouldn't expect it to, since USB support is a basic feature supported by the OS.

What OS are you using?

 

[waht]

also need to format the hard drives if they haven't been already

 

[B. Elliott]

Are you plugging these drives into on-board USB ports, or into a USB hub?

Due to different companies having their own proprietary way of supplying USB support, their capability is sometimes limited by how they are wired.

Have you looked at your IRQ settings with the drives attached?