Terrin is pink (texture)

Hi everyone I got a problem. My terrain is pink right now, an hour ago it was textured and good looking, but after I imported Top Down Assets pack and opened the scene again it shows pink. I tried closing and opening Unity but it still shows pink. Here is a picture:
alt text

As you can see I have all the textures. If someone could help me, I would really appreciate it.

Thank you!

Pink means a shader was not found. Check the console log and see if it tells you about anything missing.