Unity 5 Shader error

Hi, I been working on a project for almost 2 years, before I upgraded to Unity 5 I had never seen this error before. After upgrading to unity 5 all my terrain objects would be dark. It took me months to try fix it with no help. I ended up deleting a script that did my Night/Day and ended up using gradient Ambient Source for lighting. This made my project look so bad after spending so much money on terrain composer and other assets. I got tired finding no fix and I took the bite to delete my project and start from fresh. Its been months since I decided to use unity again,, now I started a fresh project after downloading new unity, and guess what I get the same problem again. I have no clue wtf is going on but my stress level is at breaking point im starting to learn cryengine.