HDR Will not set

What is your receiver model? Also, what is the current format of the receiver? It should be set to 1080i normal resolution. 1080p will apply to VOD as there is no Live TV with 1080p other than the few 4K channels that DIRECTV currently offers. 

Go into settings and go into the system and then display then go to HDR hit select to turn it on.  It will reload! No need to reset your box unless that does not work then press the red reset button on the side of your box and try again.

I have a standard Directv Streaming Device. The video status is set to Full HD 1080p.  The screen resolution of my TV IS 3840 X 1260p 60 Hz.

When I set HDR to “On”, it brings up a screen that offers me a choice of “Dismiss” or “Restart Now”.  It does not reload unless I select “Restart Now”.

Try checking your tv's settings it may have an on/off function that could be preventing it from turning the HDR on even tho your TV is HDR capable?  

I checked that.  My Samsung TV has a setting called “HDR+” that is supposed to “provide an optimum HDR effect based on the video source”.  I turned that on and I still have the same problem.

I just got off the phone with Directv Support and they’re going to send me a replacement streaming box.

You posted in the DirecTV Satellite Forum. Moving to the DirecTV Stream forum. 

I figured this out! you have to have your display setting on 1080P to be able to toggle the HDR option on permanently. a good HDMI cable and a modern TV as well. it's working! my issue was I was trying to use a display setting that looked better than 1080P, one of the higher refresh rates. try changing that first. it should work for you too.