Reset X Forms :

"Returns a particular XForms model to the state it was in when the form was opened. This allows the user the reset the contents of the form to their "starting point", which can increase usability of the form."
1.) So what does that mean? Ok so when you first create a primitive in 3DS Max you should notice a white "bounding box" that encases your model You can toggel it on and off with the shortcut key "J" . Notice the Bounding Box conforms to the object and is essentially undistorted.
2.) What happens is during the course of modeling you will attach, detach, extrude, rotate, and yadayadayada on an so forth. By the time you are done with your model and ready to export or whatever you may notice that your bounding box is a little off or skewed. If that is the case you need to fix it because it will cause problems in other packages and cause problems for animation. Trying to effect the element within the selction, or the pivot point can get you close to the original state. However it may not be accurate.
3.) There is a tool in 3DS Max called Reset XForms and it allows us to reset that bounding box with minimal effort. Go to the Utilities tab. (Upper left hand corner. It looks like a hammer.) Once you click on that you will see the option to click Reset XForms. Do so. When you do that a menu will appear below in the column. Choose Reset Selected and click on your model.

4.) You will notice that a modifier called "XForm" is placed on the modifier list. Your model, when you select it, will show you the projected position of the bounding box in white. It will also show you the current bounding box in orange. Right Click on the XForm modifier and "Collapse All". This will complete the operation and commit the operation to the model.
5.) You will get a warning. Click Yes.
6.) Your model should have a bounding box that is reflective of the world axis. Your ready to export/Rig/Animate.
7.) ATTENTION!!!! Some times ResetXForms flips your normals inward. They might look something like this:
8.) If that happens just go into your Edit Poly or Edit Mesh stack and select all the faces and click flip normals which is located under Edit Elements.