Convert m3d to x

Download and install the latest version of Filestar.
Right click on one or more M3d file(s) on your desktop and select Convert with Filestar.
Type convert to x in the search box.
Press Convert.

What is the difference between .m3d and .x?

Name: Model 3D; DirectX’s X file
Extension: .m3d; .x
Format: Binary
Category: 3D; 3D
Developer: bzt; Microsoft
Description: Compressed 3D model in the Model 3D (M3D) format, an open binary mesh format for games; X is a DirectX Model image file used by DirectX technology which is for 3D graphics rendering in games. The file format specifies 3D object structures for meshes, textures, animations, and objects.
MIME Type: application/x-x_file
Sample: sample.x