Help! PC only allows 1 external HD at a time?

[kreifer1]

I have a self built desktop PC running windows 7. I have 2 internal HDs and tried to connect 2 external HDs but the PC will only register 1 at a time. If I hook up the second one the power light blinks but it never shows up in My Computer or in Disk Management. I thought this might have been a power issue so I purchased a USB hub that is self powered but I have the same problem. Any ideas why this would be and what I can do to fix it? Any help would be much appreciated.

Thanks

 

[scout_03]

did you see them one at the time when connected separately

 

[kreifer1]

Yes both hard drives work individually but when I try to plug in both only the first one connect shows in Computer and Disk Manager. I've tried various usb ports on the desktop and my usb hub which is powered.

 

[scout_03]

i found something on microsoft technet ,http://social.technet.microsoft.com/Forums/fr-FR/w7itprohardware/thread/dd9cd509-f9ac-4295-a75b-863f92f5595f?outputAs=rss

 

[john the swift]

Quick question, is this a brand new external HDD that has not been Initilialized in disk management? or is this a previously working drive that has a partition on it?