Generic data file created by a specific application typically accessed only by the application that created the file may contain data in text or binary format text based DAT files can be viewed in a text editor. Security Certificate filedb Data base file. The. DIC file extension is a Dictionary file text file which can be used as an alternate dictionary on top of the Microsoft Windows Dictionary and may contain an optional set of personalized words which the user has opted to add for spell checking purposes. Directory Directory protocol associationsdll A Dynamic Link Library dll file is a support file used by one or more programs. Drive protocol associations. Microsoft Recorded TV Show file. The default program is Windows Media Center. Executable application files. Folder protocol associations. GIF Graphics Interchange Format image files. The default program is Internet Explorer. Usually associated with G By default, there is no associated program for this in Windows 7. C or C program language header file normally with. C or. CPP file. In computer programming, particularly in the C and C programming languages, a header file or include file is a file, usually in the form of source code, that is automatically included in another source file by the compiler. Typically, header files are included via compiler directives at the beginning or head of the other source file. Help filehta HTML Hypertext Mark up Language application. The default program is Microsoft R HTML Application host mshta. HTML Hypertext Mark up Language document files. The default program is Internet Explorer. HTML Hypertext Mark up Language document files. The default program is Internet Explorer. Icon files. The default program is Windows Photo Viewer. CD or DVD image file, essentially equivalent to an ISO file. Setup information files. The default program is Notepad. The INI file type is primarily associated with InitializationConfiguration File. These files are typically ASCII text with various configuration options set into sections. Image file. jnt Journal document file. Default program is Windows Journal. JPEG Joint Photographic Experts Group image files. The default program is Windows Photo Viewer. JPEG Joint Photographic Experts Group image files. The default program is Windows Photo Viewer. JPG Joint Photographic Group image files. The default program is Windows Photo Viewer. Java Script file. The default program is Microsoft Windows Based Script Host C WindowsSystem. JSE JScript encoded script file. The default program is Microsoft Windows Based Script Host C WindowsSystem. Library folder. NOTE To restore the default icons, you may need to do these as well. Shortcut link LNK files. LOG is a file extension associated with Log files. It is a text file. M2. T High definition video recording format used by many HD camcorders commonly referred to as HDV uses MPEG 2 compression to store HD video data on DV or Mini. DV tapes supports resolutions of 7. M2. TS Blu ray BDAV Video File. Video file saved in the high definition Blu ray BDAV format used for saving video data on Blu ray discs based on the MPEG 2 transport stream and supports 7. BDAV stands for Blu ray Disc AudioVisual, while the M2. TS extension refers to MPEG 2 Transport Stream. The M3. U file type is primarily associated with MP3 Playlist File. Generally known as a Winamp Playlist file, this format has been adopted by a wide variety of MP3 players. The default program is Windows Media Player. MPEG 4 audio file. The default program is Windows Media Player. M4. V MPEG 4 file extension used for videos downloaded from the Apple i. Tunes store includes TV episodes, full length movies, and music videos similar to an. MP4 file, but may be copy protected using Apples Fair. Play DRM copyright protection. A XML file that contains information about accompanying files in the same archive. Mail service. mhtml MHTML document file. The default program is Internet Explorer. A Matroska Multimedia Container file is a video format similar to the. AVI,. ASF, and. MOV formats. By default Windows 7 does not have support for opening this file type and has no association. Div. XPlayer is a good free program to install that does support playing this file extension. This download will set this file extension back to the default unassociated state in Windows 7. Movie file. The default program is Windows Media Player. MP3 sound format file. The default program is Windows Media Player. MPEG 4 movie file. The default program is Windows Media Player. MPEG audio file. The default program is Windows Media Player. MPEG movie file. The default program is Windows Media Player. MPEG Moving Picture Experts Group video file. The default program is Windows Media Player. MPEG video file. The default program is Windows Media Player. Mirosoft Common Console document files. Microsoft Windows Installer installation package file. Microsoft Windows Installer Patch file. MTS Mad. Tracker 2 Sample File. High definition MPEG Transport Stream video format, commonly called AVCHD Advanced Video Codec High Definition used by Sony, Panasonic, and other HD camcorders based on the MPEG 2 transport stream and supports 7. HD video formats. MTS files can typically be opened and edited using the software included with Sony and Panasonic HD camcorders. The default program in Windows 7 is Windows Media Player. System Information Fileobj Object file. Open Type Font file. The default program is Windows Font Viewer. Package Package protocol. Dial Up Phonebook file. The default program is Remote Access Phonebook. Portable Document Format PDF is a file format created by Adobe Systems.