external laptop drive not detected

[oxocubeman]

I have 3 external laptop drives and my desktop and 2 laptops dont "see" them. My old dell latitude laptop shows them everytime. Why? different current at the usb perhaps? i use dual leads for the drives everytime. If just a single osb lead is used the drives just click. How can i get them to work on all my computers?

[mrt9888]

You will need to use a usb port with more power or a usb cable with two connectors.

[silverdisk]

I am using the two way lead and how do you find the output of the usb socket?

[peterb]

The USB specification states that a USB port will supply a maximum current of 500mA. However some laptops struggle to provide that (even using a dual headed connector) - the only realistic solution is to use a powered USB hub.