I had a video on YouTube give me (and every other person that viewed it) the message “An error occurred. Please try again later. Learn more”. This happened, of course, on my most popular video. Just that one video.

No promises that this will fix your issue, but here is what fixed mine.

1. Go into your Creator Studio and then into Video Manager.

2. Select the Audio tab.

3. Select Revert to original, and then click Save.

4. Wait for YouTube to process the changes, and hopefully you’re done.

Many people suggest reuploading the video, but then you lose all of your stats for the video. If all else fails, try this fix. It takes 30 seconds to try it, and is harmless. I hope this helps somebody.