Where is the config file?

Depending on whether you use the installer version or the portable version, you can find VolumeControl.json in one of two locations.
The location of the config file cannot be changed.

If volume control is running, you can open the config file by R+Clicking on volume control's system tray icon and selecting Open Config.

Installer Version

%LocalAppData%/radj307/VolumeControl/VolumeControl.json

Portable Version

The same directory as VolumeControl.exe

Where is the log file?

The location & name of the log file can be changed on the Settings tab in the main window.
If you changed it from the default, you can find the path by searching for LogPath in VolumeControl.json.
Otherwise, the default locations for each version are listed below.

If volume control is running, you can open the log file by R+Clicking on volume control's system tray icon and selecting Open Log.

Installer Version

%LocalAppData%/radj307/VolumeControl/VolumeControl.log

Portable Version

The same directory as VolumeControl.exe