Models referencing textures

Whilst working on my current project, we’ve come across an issue with models and their textures, sometimes when the model is being put into the project, as soon as the required material is in the same unity project, it will reference it to the UVW map instantly, and the texture is simply applied and it works, however for others it is asking to drag and drop the texture, can anyone explain what difference of process is required to make this occur?

make sure import material is set to per texture. make sure the imported texture is not a psd photoshop file. make sure a material with the non-psd texture is applied to the object in your 3d package before export. make sure the unity texture is in the exact same folder as the fbx model.

following the above gets me auto assigned textures to materials everytime, with no duplicate materials