This is normally caused by the Windows MP3 codec not being installed or being disabled.
First, make sure you have the latest version of Windows Media Player install from
http://www.microsoft.com/windows/windowsmedia/download/AllDownloads.aspx
If that doesn't solve the issue and you are running Windows XP, you can verify that the MP3 codec is enabled by doing the following:
- Click on your Start Menu.
- Click on Control Panel.
- Click on Sounds, Speech, and Audio Devices.
- Click on Sounds and Audio Devices.
- Click the Hardware tab.
- Double-click Audio Codecs. (figure 1)
- Click the Properties tab.
- Double-click Fraunhofer IIS MPEG Layer-3 Codec. (figure 2)
- Select Use this audio codec. (figure 3)
- Click OK and close all windows.
- Start MuvAudio and try converting your files again.
Figure 1:
Figure 2:
Figure 3:
