how change a file .MAX in a file .ASE with 3d studio max ?

how ?

I think File->Export should do it, just change the filetype from the default (I think 3ds) to ase. If Export doesn’t do it, try a Save-as.

thanks it’s that !

PS : the default name is .max

You are correct, when saving a file the default extension is .max. However when exporting, I believe the default is .3ds, which was the point of my comment above.