[Solved] Blender Model Texture Problem

[stonecutter]

Well now im creating custom models and i am working on a mine entrence ...

i exported it as a .dae and open it with the model viewer ... all works fine but it shows the texture of the model in grey. I used a brown texture of the rocks from amnesia but in the modelviewer its still grey .. but in blender it shows the right colour ! Anybody got an idea what could be wrong ?

Thanks a lot !