You're here because you have a file that has a file extension ending in .smf. Files with the file extension .smf can only be launched by certain applications. It's possible that .smf files are data files rather than documents or media, which means they're not meant to be viewed at all.

Files in the SMF format contain audio data with effects, and this file format is integrated with similar technologies and functionalities as files with the MID extension. Audio tracks with the .smf extension can be played using the Apple QuickTime application, and this multimedia program has a version compatible with Microsoft Windows-based systems aside from another version developed for Mac users. The MIDI Manufacturers Association integrated MIDI specifications into the SMF file format during its development. This means SMF files can also contain different tracks combined from different audio tracks stored in several SMF files, which also means files in the .smf format can be combined and converted into one audio track in more popular formats that can be viewed and used with more digital video and document presentation development software, multimedia applications and digital audio players. This provides users with a means to separately add effects to each track and make modifications on others before combining them to play as a single audio track. Some of these effects and modifications may include volume and pitch adjustments, distortions and reverb, panning and timing edits among others. There are third party applications that can convert SMF files into the MIDI format for wider cross compatibility support for more audio editing applications.

Launch a .smf file, or any other file on your PC, by double-clicking it. If your file associations are set up correctly, the application that's meant to open your .smf file will open it. It's possible you may need to download or purchase the correct application. It's also possible that you have the correct application on your PC, but .smf files aren't yet associated with it. In this case, when you try to open a .smf file, you can tell Windows which application is the correct one for that file. From then on, opening a  .smf file will open the correct application. Click here to fix .smf file association errors

Be careful not to rename the extension on .smf files, or any other files. This will not change the file type. Only special conversion software can change a file from one file type to another.

A file extension is the set of three or four characters at the end of a filename; in this case, .smf. File extensions tell you what type of file it is, and tell Windows what programs can open it. Windows often associates a default program to each file extension, so that when you double-click the file, the program launches automatically. When that program is no longer on your PC, you can sometimes get an error when you try to open the associated file.