Use free software like or FFmpeg to convert the problematic video into a modern format (H.264 + AAC in MP4 container). This eliminates codec issues entirely.
To play files on MX Player, you must install a custom codec package. VMD is an older proprietary video format used in legacy optical media and archival footage that MX Player cannot decode natively. 1. Identify Your Required Codec vmd codec for mx player
After you install the official custom codec, MX Player gains support for these additional formats, which are often mislabeled as requiring a "VMD codec": Use free software like or FFmpeg to convert