Installing NuGet Package: "Access to the path 'c:\Documents and Settings' is denied."

First, I must ask for patience... Although I was a real paid developer 15 years ago, now I own low-tech business and haven't touched it in a long time. Back in the day VB.NET was new and I did maybe two medium-size projects with it. So, I'm behind the times and all my training is ancient, but now I need a little project for my business and I only trust myself to get it done right.

So now I've installed Visual Studio Community 2019, and I'm running Windows 7. (Because it still ain't broke.) and I'd like to use the Google Calendar API in a WinForms app. (But this question could probably apply to many API's.)

I've watched this video (which is from a C# guy but the code differences are trivial.)

https://youtu.be/qNdpWph4Pi8?t=162

And as you'll notice this link goes to 2:42 in the video, which is where it fails. The output from the Package Manager says:

Attempting to gather dependency information for package 'Google.Apis.Calendar.v3.1.49.0.2086' with respect to project 'WindowsApp1', targeting '.NETFramework,Version=v4.7.2'
Access to the path 'c:\Documents and Settings' is denied.
Access to the path 'c:\Documents and Settings' is denied.
Gathering dependency information took 45 ms
Attempting to resolve dependencies for package 'Google.Apis.Calendar.v3.1.49.0.2086' with DependencyBehavior 'Lowest'
Unable to resolve dependency 'Google.Apis'. Source(s) used: 'Package source', 'Microsoft Visual Studio Offline Packages'.
Time Elapsed: 00:00:00.3002072
========== Finished ==========

What I've tried: Lots of browsing, and a few dead ends. I am logged in as Administrator, I have un-hidden that folder, I have allowed full control (which I probably shouldn't) and I am aware that in Windows 7 that folder is just a shortcut, but it seems the package itself is pointing to that folder because I certainly didn't tell it to tinker with it. I'm out of ideas. Any guidance on what to try next? I kinda hope the answer isn't "Get Windows 10".