Reflection Probe Issue (Bug?)

I was using Reflection Probes, It misteriously happened to some other test probes as well but I've deleted them and these two you see on the Hierarchy were perfect, but today I rebaked them all of a sudden, all out of nothingness, the Probe's Mirrored Sphere became this pink strange looking ball of "what?", also the reflections are all messed up and I cannot understand why or how. Also there is this strange error shown at the bottom of the image.

I'm using Unity 5.6.0f3, Is this a bug? Or some other thing?
Why did it Happen?
How do I Fix it?

Thanks;
Arthur

 

This is a bug. You can find multiple topics on this in this forum.