I followed the instructions VERBATIM, yet it won't work. As soon as it's plugged in, the lights come on, but then just the "power" light blinks for a few seconds, then it's off. No button on this earth will turn this box back on, unless I unplug, then plug it back in. The outlet works fine, what is the problem? It won't stay on long enough for anything to come on the screen. What can I do, other than have a tech come out?
While I don’t have an answer to solve this myself, I wanted to comment that the exact issue started for me yesterday (11/24).. Nothing I do will power up this box. When unplugged from power and then plugged back in, the three lights on the box will come on, flash a bit, then the power light will flash alone for a bit and POOF, it shuts off.
@jgilpin89 wrote: ... just the "power" light blinks for a few seconds, then it's off. ...
What is the cable box model number? Some won't power up if they don't detect a signal from Comcast. If you can't get it working, you will need to have a service tech visit.
If you want to troubleshoot this yourself, please see the cable modem Connection Troubleshooting Tips.
If you can't find the problem or you'd rather have Comcast do the troubleshooting, call them at the phone number on your bill or 1-800-Comcast, or or use one of the options on https://www.xfinity.com/support/contact-us/. If they can't fix the problem remotely, insist they send a tech out to identify the cause and correct it.
If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device, or anything outside your home, you shouldn't be charged.
My problem has been solved. Just as I suspected, it’s the box. I had an ‘older’ model which I was told is being fazed out thus my issues with the box not responding/loss of features.
Hope this post helps others who have also incurred this issue recently.