Hi Kand S,
I understand how frustrating this must be, especially since the same videos played correctly on your previous computer.
The brief "codec needed" message suggests that the affected videos may be using an audio codec that isn't installed or supported on your new PC. One possibility is AC-3 (Dolby Digital), which may not be included by default on some clean installations of newer Windows 11 versions.
Could you check one of the affected videos by right-clicking it, selecting Properties > Details, and looking for the audio codec information? Once we know the codec being used, it may be possible to install the appropriate extension from the Microsoft Store or obtain the codec from the device manufacturer. I would avoid downloading codec packs from unfamiliar websites, as they can sometimes introduce additional playback issues.
For the issue where only one video plays at a time, try opening Media Player first and then adding multiple videos to a playlist or queue, rather than opening each file individually.
When you have a chance, please let me know:
- The file extension of one of the affected videos (for example, MP4, AVI or MKV)
- The audio codec listed under Properties > Details
- The exact codec message or error code, if you can capture it
That information should help determine whether this is a missing codec issue or another Media Player compatibility problem.
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