USB wont work. It comes up with a pop-up saying"USB NOT RECOGNISED"

what to do, what to do.

Try this.. Just keep the device connected and then restart your system.. What sort of a divice is it anyway..?? And which OS are you using..??

did you try installing the driver?

I have this problem with my external drive also. It works on the old Windows XP pc. It has no drivers to install. No updates online. It won't work on the new Win7 PC. All the other USB devices work. (Printer, Ipod, Camera, mouse, Keyboard, flash drives). I've tried powering down and restarting.

this isn't a solution but it altleast worked for me....
turn off your computer
plug in the external drive or ur usb or what ever u have
then start the computer and u'll see that it works now :-)