Welcome to the community, @Joseph!
I'd recommend you to go to
Disk Management in Windows and check if your WD Elements external hard drive is recognized there. Is it a brand new WD Elements or do you have data on it? If you still aren't able to see the external HDD there, try connecting it with a different USB cable and to a different USB port on your Windows XP computer. If you have access to another PC/laptop, try the drive there as well to see how it will get detected by the other system.
Keep me posted!
SuperSoph_WD