Why is my project suddenly Turquoise colour and semi- stuck/frozen?

Hi,

I've been busy trying to learn Unity and I'm currently building a scene. I had a crash earlier and when I restarted the computer and the Unity, everything in my project (excluding prefabs) has turned Turquoise.

Is this something to do with Lighting and Baking?

I ask because after staring at this screen for 10 minutes it suddenly said in the bottom right hand corner, Preparing to Bake (or for Bake). After another 10 mins of nothing happening I quit Unity. Before I go on, let me explain the behaviour of Unity.

Whilst looking at my project I was able to click on a few menus but I could not select anything in the Heirachy, I couldn't select anything in any menus. It was like it's not crashed (which is why I think it has to do with something to with Baking or other task) but sort of has crashed.

Anyway, I then decided to uninstall Unity and redownload it. Just in case something was wrong. I've just tried my project and it's exactly the same situation. I have a backup of all my stuff and will try that in a minute but all the other scene saves ( I have been saving a new scene when I get to a certain point ) in a project are effected in the same way.

Here's what the project looks like...




I also have this error.




I have had this error since I started using Unity. And I get this error when I load a brand new project and use the default windows. What does this error mean? I can hardly believe the factory release state of Unity would have problems loading it's own editor layout?

Many thanks and I hope someone can end this frustration for me

Jono