Material doesn't have a texture property '

After a crash in Unity I started to have tons of this message that has been reported in other Forum Questions with no answer:

Material doesn’t have a texture property ‘_MainTex’
Applications/buildAgent/work/6bc5f79e0a4296d6/Runtime/Shaders/Material.cpp at line: 562

Someone could help?

Believe it or not, I quit Unity, restart my Mac, started Unity and VOILÀ, ALL WAS SOLVED.