All my materials are pink!

One day i opened my project and everything with a texture was pink. I got this error message

Shader error in 'Standard (Specular setup)': failed to open source file: 'HLSLSupport.cginc' at line 128 (on d3d11)

Compiling Vertex program with SHADOWS_DEPTH Platform defines: UNITY_ENABLE_REFLECTION_BUFFERS UNITY_PBS_USE_BRDF1 UNITY_SPECCUBE_BOX_PROJECTION UNITY_SPECCUBE_BLENDING UNITY_TEXTURE_ALPHASPLIT_ALLOWED

I've tried to reinstall multiple times and have had no luck. I think it might be that there is no texture on the object but I can't find the default textures! If that is the problem please give me a link.

Here's a picture of what it looks like, please help! All of my projects are like this.