I have seen where the installation of VDH seemed to complete successfully but it actually
didn't. The solution is to simply install it again. To find out where to install it
from, click this:
https://groups.google.com/g/video-downloadhelper-q-and-a/c/BzPLK2YyL-s
Make usre you read the first 2 paragraphs there. After that, search for "various pieces"
within the text of that web page. That will give you a link to an explanation of where
to find the various pieces of VDH. You want to install the 8.0.0.0a2 beta of VDH. It is
a much improved version. At some point, it's supposed to get approved by Mozilla. At
the moment, it has not yet been approved. So you can get an advance copy by using the
beta.
When you install VDH, the final step of the install is a screen saying, "Congratulations,
you have just installed . . ." When my installation failed, everything happened as it
should except the congratulations screen. On my second attempt, I got that & everything
was good after that. So be sure you get that congratulations screen when you install.