Why is my terrain all grey?

I was trying to delete stuff to get rid of errors and it caused my terrain to become grey, along with trees and my road textures i had on mesh planes. What can I do to fix this? I HATE that it autosaves…

I backed up the project folder but when I loaded it on another computer to see if it worked, it just imported all the assets…

You should be able to restore everything you deleted from the Project folder, as long as you haven’t emptied your Trash. It should all be in there.