i have a dell laptop latitude c600, when i try to connect usb 2.0 massstorage devive ( which is a hard disk of segate in external casing )my computer does recognize it as an exteranl usb device but the drive letter does not appear because my notebook usb is 1.1 , what should i do ?

It's not the fact that your notebook is 1.1 that it's not showing, it's that a lot of USB hard drives need external power to work with some notebooks. If it is a large hard drive (20GB or greater) You'll need to use a separte power adapter or a cable that gets power from your PS2 port to power it for the laptop. The notebooks USB bus is under powered. Musky If the voices inside my head paid rent, I'd be rich!

The device may have come with drivers to allow it to be recognized. Does it show up as a folder? You can get a USB2 card for your laptop. I'd recommend it.

well i have the hard disk installed in an external casing that has its own power . so it simply means that its not the power issue but something with usb 2.0 and usb 1.1 ...... ???

My USB2 HDD shows up as a drive when connected to the USB 1.1 of my laptop. I did have to install drivers on my laptop (supppled with the HDD) to get it to do this.

Is this External drive partitioned and formatted?

I didn't realize that you have an externally powered HD case, so your right, power shouldn't be an issue. Does the drive show up when you go into "Administrative tools/Computer management/storage/disk management"? If it does, then you may need to partition and format it as Othehill mentioned. Musky If the voices inside my head paid rent, I'd be rich!