.fil - File template
.application - ClickOnce deployment manifest file
.mobi - Mobipocket eBook Format
.x_t - Parasolid document
.wmz - Windows Media Player skins file
.mdf - Menu definition file
.sch - Schematics schematic file
.-5 - Audio Utility Tuningwrench compressed file
file extension AC - Mopac Cartesian chemical modeller output file
File extension AC description:
Probably old file extension or not supported application.
