What is this 'IMS not registered' error?

[AC Question]

What is IMS not registered

My note 4 sayd IMS not registered. What is that

 

[Guytronic]

Re: What is IMS not registered

IMS has to do with multimedia over the cell system.
It's essentially a communications subsystem that has to with video calls or features that aren't in place yet for any particular carrier.

The technology is there it's evidently not used by major US carriers.