YouTube API, Can I add a developer tag to an uploaded video?

My youtube videos have no developer tag and now I want to add one for them

I can get the videoEntry for those videos I can add new developer tag as new MediaCategory I can add MediaCategory as new Category to my video entry (displayed fine)

After I called VideoEntry.update() and use my own function to display the developer tag, it shows me the video has no dev tag. The function is working since I tested with my newly uploaded video(with dev tag during uploaing process)

My question is, 开发者_JAVA技巧Is it possible to add a developer tag after a video had been uploaded.

If possible, What's the essential steps? Do I use VideoEntry.update() ?

I currently have the same problem. According to this, you cannot add developer tags after the video has been uploaded. I do not know why Youtube has this restriction.