Can't connect external hard drive to Dell Latitude D600

I've got an external hard drive (WD Passport) and I am trying to connect it to my Dell Latitude D600 laptop but it doesn't work. At first it didn't see anything in the USB port but after connecting and disconnecting it a few time it finally recognised the new hardware. But I didn't manage to use it as it shortly have me an error message "Power Surge On Hub Port. One of the USB device has exceeded the power limits".

I have tried the external hard drive on my husband's laptop (a Compaq) and it worked fine from the start.

Does anyone know what the problem is? I know this Dell is old (I've had it for 5 years) and I need to upgrade but I've got the external hard drive to get all my files, photos and music from this laptop. If it had a CD writer I could have put everything on CD's but it's that old that it only has a CD player :(

If anyone can help it would be great.

Thanks.