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The model will need to either be adjusted in the original CAD appliaction to work on the platform, or it will need to be submitted as a manual request to the 3D Service provider. You can access a guide to several of the most common problems here.
Simplify Your 3D Model
3D printing is created from mesh representation which is an approximation when modeling using NURBS or solid geometry.
When creating the triangulation remember to consider the number of triangles the file has when saved:
Using too many triangles can very likely restrict the 3D printing process (this is due to technical limitations based on resolution).
Extremely few triangles can instead result in a rough or low resolution model.