Question Entire Project Turned Black and White Checkered after loading project up. Textures missing too.

My project was filled with terrain pieces that have textures of grass, snow, and trees painted on. Loaded up project from last night and this is exactly what I've come back to. It doesn't appear to be anything I have manually changed, and I've checked the lighting. I also lost a few of my tree textures in the tree paint brush. I am willing to post more of my project, but I don't know where to start. Any suggestions are greatly appreciated!

 

Think I figured out how to fix it, I randomly had a bunch of textures and materials corrupted so all I had to do was re-import them and they were instantly readded to the terrain too. Still missing some of the textures and materials but I think that is because I forgot where I originally got them from.