Flash in my Nikon D800E works only when the liveview is off. Why?

The flash in my Nikon D800E works only when the liveview is off. Why? - 1

That's the way the firmware is designed. Download a patch, they're available.

If you need the flash, then light is low. If light is low, you shouldn't be using liveview like a cheap point and shoot. Holding the camera during liveview is unsteady and will lead to motion blur in low light.

For one thing, the flash can't provide continuous light.

(Hint: That's Why it's called a "flash".)

So, since it would be Useless in live view mode,
it is Disabled in that mode.

I'm trying to think of a situation where I would be using a flash in the live view mode. I can't.

Whether I'm using an onboard Nikon SB flash or trigger or using studio flash units and a trigger, I have never been in the live view mode.

I just tested my Nikon D800e in live view and the flash did fire.

I even tested the flash in live view with the shutter set to 1/500th second, far beyond the cameras flash sync of 1/250th second and the flash still operated in live view.

My I ask why you are shooting in the live view mode? Certainly, you are not using the camera like a point and shoot and attempting to hold the camera at arm's length when taking photos, right?

Lowbat?