Issue with YoutubeExplode – Transcript Not Working on Live Server

[HarshDarjiHack]

Dear Tyrrrz,

I hope this message finds you well.

I'm currently using the YouTubeExplode NuGet package in my .NET 8 application to retrieve YouTube transcript data. Everything works perfectly in my local development environment, but I’m facing an issue when the same code is deployed to a live production server (IIS).

Specifically, the following line is throwing an exception:
var manifest = await youtube.Videos.ClosedCaptions.GetManifestAsync(videoId);

The error message is:
Video '{VideoId}' is not available.

Details:

1. The video is public
2. The video has closed captions (transcript) available
3. I am able to retrieve the captions locally without issues
4. The same video ID fails on live server
5. No VPN or IP restriction in place
6. IIS server has internet access

This leads me to believe there may be an environmental or network-level issue, but I wanted to confirm:

1. Are there any known network restrictions, rate limits, or firewall/proxy settings that might affect YoutubeExplode on production servers?
2. Does YoutubeExplode require any special headers, TLS versions, or user-agent configurations that might differ between environments?
3. Is there a way to better diagnose or debug the root cause of this specific error on the server?

I would really appreciate any guidance you could provide to help me resolve this issue.

Thank you for your time and for providing such a useful library.