Cant connect my samsung fascinate verizon to pc to transfer files?

[Corazon R]

I have my phone connected to my pc with usb. My phone shows me the option to mount. I click mount and I do have my debugging on. My pc sees my device. In the my computer it shows removeable disk e anytime I connect my phone with usb. I click on it and it says please insert disk into drive e. My computer is windows xp. I have been stuck and cant figure it out. I have a laptop and when I connect my phone to transfer files it works fine. My laptop is windows vista if that makes a difference