I'm trying to upgrade my tivo Series 3 HD to a 1TB HD (Hitachi HDT721010SLA360). I'm using a Win 10 PC and WinMFS 9.3g. I connect the Tivo drive and the Hitachi both via Serial ATA on the same cable from the MB and power cables from the power supply. When the computer boots up, the Hitachi has been assigned a drive letter (D) and the Tivo drive has not been assigned a letter and is not available as a volume. In Device Manager I can see all 3 of my drives are recognized and have been assigned Bus #'s. My solid state main computer boot drive is (0), the Tivo drive is (1) and the Hitachi is (2). I have changed WinMFS to run as administrator in the properties. When I run WinMFS and go to Select Drives, I check the "Show Mounted Drive" box and my Hitachi appears as #2. I select the Tivo #1 as Drive A, then click the "Select" Button. I then go to Tools > MFSCopy. My Tivo is listed as the Source drive but I have no options under Destination Drive? Only "None" in the drop down? What am I doing wrong? One last thing...If I select the Hitachi as the Source drive, the Tivo drive is now selectable as the Destination drive. Not sure if that helps, it doesn't help me. Sorry for the long post but I figured I'd try to give all the info I can and answer as many questions as possible up front. Any thoughts?