# Song Versions

Versions of a song can be created and reverted to later. These versions include the song file, as well as the MIDI and .aem files opened in the tracks.
Typical uses for versions include:

- Create a version before making major changes to the song, so you can revert to the previous version if the changes don't work out.
- Try different mixes and store each as a version. You can not only change mixer settings, but also edit audio and MIDI tracks.
- Create a version of any mixes you send to someone, just in case they later decide the older version was better.

### Create Version

The Song menu's Create Version option opens the Create Version dialog, which lets you enter a name for the new version. If there are unsaved modifications in the song, you can choose whether or not to include them in the version. This can be helpful if you open a song and start tweaking the mix: if you think you're onto something good, you can still create a version of the song as it was when you opened it, just in case the new mix doesn't turn out well after all.

### Revert to Version

The Song menu's Revert to Version option lists all available versions. Tooltips show information about each version, such as the date it was created. You can revert to a version by clicking on it. If there's no version that matches the current state of the song, a new version representing the current state will be created automatically. These automatically created versions are named "Autosave Version 1", etc.

### Autosave

Some versions are created automatically:

- Autosave (safety backup): A version is created every 15 minutes. If the computer crashes, you can reopen the song and revert to this version to minimize lost work. The version is created when transport stops.
- Autosave (discarded version): A version is created if you choose to discard changes when closing the song. If you change your mind, you can reopen the song and revert to this version.

Note 1: Autosave versions aren't created until the song has been saved at least once.

Note 2: Audio files themselves are not stored in version files, so if you edit an audio file using a third-party editor, all versions using that file will be affected. To avoid this, make a copy of the file and edit the copy.

Note 3: The versioning system assumes there is only one song per folder (i.e., it assumes every version found in the folder belongs to the current song). This is the case with MultitrackStudio 5 or newer. For older songs, you may want to check this before reverting to a version.

Note 4: Some third-party demo plugins display a "demo limitation" message when plugin settings are saved. These messages will appear whenever a version is created.

Under the hood
A version file (.hdrversion file extension) is a song file that also contains the .mid and .aem track data.