Gentlemen, I have fought back and forth on whether to upgrade my TIVO HD but finally bit the bullet, took apart my Seagate external 1TB HDD, and went for it last night. THANKFULLY I listened to the warnings about "mounting" the original HDD in Windows. I was using Windows7. PLEASE READ the instructions because after a couple of failed attempts in Windows7 I noticed that WinMFS will only work in WinXP SP2/SP3. I installed a single HDD in my computer and took twenty minutes to install XP SP2. I did not install any drivers and fresh off of the first boot I ran WinMFS and the original TIVO HDD was recognized. I then proceeded to run my backups first. After successful backups I ran the MfsCopy. I did miss the step to make the NEW HDD the primary or "A" but my system booted as if it was straight out of the box. All features worked but the network configs. I had to verify my network settings and connect to the TIVO network. one word about this TIVO forum and source of information: !~AWESOME~! thank you guys SO much for making yourselves available The result of this is that I can travel and be busy but STILL record ~129 HOURS of the Olympics! I LOVE it!