I am using a Lenovo Thinkpad X201. I have a problem on the my 40GB iPod which works with USB 2.0. I was using only one usb port for connecting my ipod and copying music in that. The issue happened here that recently there was blue screen on my system. After a reboot my ipod is not detecting the ipod. I found a yellow mark on the usb in device manager. What does this mark indicates.