You should be reading other threads here updated within the past 24 hours. You should
also hunt down a thread with the title "How to download from YouTube." Look for a post
within that thread dated July 17. That describes a step that you need to have executed
one time since you got VDH 8.0.0.0 or any of the betas numbered 8.0.0.x. Removing &
reinstalling VDH is probably not a useful exercise. However, your license number is
something you should keep in a safe place. Keep it hidden. Don't share it. But keep it
readily available. Occasionally, the license becomes locked. To unlock it, look here:
https://groups.google.com/g/video-downloadhelper-q-and-a/c/BzPLK2YyL-s
That one is worth bookmarking for frequent future reference. On the subject of a locked
license, just look for "locked" within the text of that web page. If you don't need that
advice now, you could do worse things than read it anyway, just to have it in the back of
your memory should the time ever come when you need to unlock your license.
If you were to uninstall & reinstall VDH, you would just register it again the same way
you did the first time. It's no big deal. The license is for life.