Needed to add my experience here as this is the only method that has worked to get my 120gb back on live. Here are a couple things I have tried after being banned for switching out my HDD back in Oct.:
1. Using banned large HDD, Flash in new eeprom - banned withing 12 hours
2. Reconfigure sectors on banned large HDD using blank disk.bin, flash new eeprom, recover OLD gametag - banned withing 12 hours
3. Reconfigure sectors on banned large HDD using blank disk.bin, flash new eeprom, create NEW gametag - banned withing 12 hours.
3. Reconfigure sectors on banned STOCK HDD using blank disk.bin, flash new eeprom, create NEW gametag - this worked for about two weeks until I wanted my large HDD back, so I did the following:
4. Backed up disk.bin (with unbanned account info) and drive partitions from unbanned STOCK HDD, reconfigured banned LARGE HDD using the valid disk.bin from my stocker, FTP'd drive partitions, flashed new eeprom, transferred account from memory card - banned within 12 hours.
5. About a week ago I put in a brand new 120gb HDD, did a F: install using Slayer's 2.6, flashed new eeprom, created new account, and I've been good ever since. I did the Halo2 update yesterday and I'm still on this morning, so I figure I'm good.
