I have an HR21-700 with a bad hard drive. D* replaced the HR21 with an HR22-100. D* says I own the HR21, and they asked me not to return the HR21. I liked the HR21-700 which is not under any warranty. Is it possible to replace the bad 320 GB SATA drive with a new larger drive? I found discussions on replacing drives, but none indicate how the drive gets formatted or if the unit will work with a larger capacity drive. Please point me to the information. Thanks!