I was cloning a 40G hard drive to a 80G hard drive keeping the same sized partitions. The balance of the 80G hard drive would be unallocated. At the end of the process, the "PRESS A KEY TO REBOOT" message was displayed. After pressing "A KEY," more than once with no result, I used the power switch to shut down the computer. Upon restart, no hard drive was detected. I removed the 40G hard drive from the computer. I installed the 40G hard drive in an ADS USB 2.0 enclosure. I installed a previously cloned hard drive in the computer. The computer was successfully rebooted. The 40G hard drive was not detected. The operating system being used is Windows 2000 Pro. Using the Disk Management feature, the 40G hard drive shows up as unallocated. If you please, it was erased. On the other side of the coin, the 80G hard drive was cloned and works just fine. This was the third time the "PRESS A KEY TO REBOOT" message has been displayed, but the first time the hard drive was erased after turning off the computer with the power switch.