I tried all of the above and still nothing. I did call Directv and talked to Technical support. First person I talked to said they were going to format my hard drive. When I explained to them that is not possible because I do not have a DVR we got disconnected. Luckily, I was able to get ahold of another Tech support person right away. I explained to them the situation, told them I've left the receiver unplugged all night, forced downloaded the new software again and just let it wait. I said I pretty sure my software got corruped. We ran one more reset with the sat cable unplugged and still never got an error. I think he agreed with me that the software was corrupted and agreed to send out a new box for free. I did not even have to pay shipping. Thanks for all you help here.
I'm experiencing your same problems, my H21 was rebooting and had no signal and no data available, while my HR21 had some lock ups and reboot issues but the signal was alright.
I'm on a Protection Plan so I called the technician, he came here on Thursday, checked the satellite, and decided to replace the LNB, he replaced the HR21 with a brand new HR23 and everything is fine with it now, but the H21 had the same signal problem after downloading the update.
He replaced it with a brand new H23 and after the software download everything was fine.
Today I have the same problem, no signal and no guide, it's trying to download the Advanced Program Guide and it has been stuck on 0% Complete for a while.