I have a Pavilion Elite e9280t running Windows Home Premium 64. The original hard drive (750GB Seagate Barracuda) was causing problems, so I replaced it with a new 2 TB WD Caviar Green drive and performed a system restore from the backup disks I made. The BIOS is version 5.29.
While I was able to reinstall Windows, I am not able to receive Window Updates and receive an error message along the lines that the Windows Update service is not running and I should reboot. I did that several times, and checked services.msc to make sure Windows Update was running, but I was still unable to receive updates. I then performed another system restore, and I have the exact same problem.
I've seen some suggestions online that really large hard drives may cause bizarre problems, but I am really at a loss at this point.