Whats a codec?
Codec stands for “COmpressor/DECompressor”. Every compressed video file uses a codec to decompress the individual frames for playback. There are a great many codecs. Some come with Windows, others must be downloaded and installed before you can play back the video. Some codecs are not compatible with DirectX, which is what ‘AVI to VCD / DVD’ uses to decode the video frames, in which case you will not be able to encode the video using ‘AVI to VCD / DVD’. Try getting the latest version of the codec, it might work with ‘AVI to VCD / DVD’.