Sounds like a software issue. You now need OS 6.4a to boot. What version are you running?

The System Information page indicates that the software version is : 3.1.1c01-2-351.
Model SD DVR80. It was last operating perfectly within the past few months. Your input is greatly appreciated. Thanks for responding to my posting. I'm 'stuck' in an RV away from home and 'live' with my TV. I only have a cellular phone. How would I go about downloading/installing any updated software?
Gary R

You would want to send us the drive to have the software loaded or you'd want a new drive, which would come with 6.4a. See:

http://www.weaknees.com/hu80.php

and

http://www.weaknees.com/misc.php

Well, you need a phone or send to weaknees. However, if there is anyone out there with the same problem, I discovered by accident a solution. My old DVR40 (new, out of storage) was being setup to replace a burned-out DVR80 and I couldn't get it to reboot. Over and over again stopping at 60%.

Here's the solution:

Disconnect Sat1 cable, reset, booting, will go fully up and eventually to the message "Couldn't acquire Sat1" or some such. Hit the "Directv" button at top of remote, go to Settings, then to Phone, Make a Daily Call, and wait.The update will start downloading and may take 12-18 hours depending upon your modem connection. The key is to dial one of the local numbers given you, but choose "1" + "Area Code" then the local number; you get a firmer connection that way (learned this in another forum). I let it download from 9:00PM until it finished at 5:30am, and, Voila!, 6.4 was installed over 3.1.1c01-2-351. Up and running great.

This should be a sticky here for older DTV TiVo's Series 2 at least that get stuck at 60% acquiring signal. But then weaknees would lose money by you not having to send it to them to load 6.4a. But my method worked perfectly.

FYI.

That's quite a long dial-in! But maybe it just forced the OS download via phone since it had no satellite connection. Good tip.

The only way to get the 6.4a software when you have the 3.1.1 installed is over the phone, not the dish, and I've read of others having to wait 24-hours for the d/l to complete; meanwhile, if you have the land line phone, your phone is blocked/busy for hours and hours. Also, if you get a call it stops the d/l. So I waited until 9:00pm and just let it run all night. Having only the Sat2 connected "forced" the old software to load from that Sat with non-acquire message but let me get to DTV Central and then to settings. Very frustrating event...

Tried this on mine as I was having the same issue, but hitting the DTV button just got me a beep, wouldn't let me in the menu to make a call, so it just stopped there. Re-plugged the cable to sat 1 and went back to 0% on downloading information, ran quickly up to 70% then stalled again. Seriously frustrated after messing with this for more than a week (I don't actually know what software version is loaded, can't see how to access that information.) Anyone have any thoughts????

PS hitting the 'thumbs up' key displays more info on the progress during this acquiring info step. Among other things, it says 'Networks 0 of 2' today, it's once said 1 of 2 and also 0 of 1. Anyone know if this is significant? APG numbers keep rising, albeit slowly, and with no indication of target (ie it says xxxx/0 always, never giving me a number on the denominator side.