File with a .SET extension contains settings or configuration of a program. It is a general format, utilised by different sorts of programs and its structure is not fixed. SET files should not be modified manually, in order not to disturb application’s functioning.

Software utilising SET files is diverse, these are, for instance, Alpha Five, Autodesk AutoCAD, Corel Painter, Diablo II or Nikon Capture. SET files are loaded usually when an application is being loaded.