Thanks, that solved the error.
Now I'm getting a response that contains an error:
{<|"domain" -> "global", "reason" -> "authError",
"message" -> "Invalid Credentials", "locationType" -> "header",
"location" -> "Authorization"|>}
When I ran:
$so = ServiceConnect["YouTube"]
... a couple of days ago, I followed your above instructions and checked the box for it to remember. When I evaluate $so = ServiceConnect["YouTube"] now, it doesn't launch the web browser but instead immediately returns a ServiceObject[...], that when used, results in the above error.
