In Visual Studio 2017 the Extensions and Updates ... option within Tools does not open and gives error message

I reinstalled Visual Studio 2017 (I tried several times to get it, I had to delete some folders that contained the name Visual Studio to be able to reinstall, otherwise it did not proceed), after the reinstallation, when I go in TOOLS and click on EXTENSIONS AND UPDATES, gives the following error:

What can I do to resolve this?