Can you please provide some more detail? Are you signing in on the website or trying to sign into the GoToMeeting software? What exactly happens, is there any error message?
I am having this same issue. When I was logged into the Hub, I selected Start to join my meeting. When the desktop app popped open, the "Sign in now" button wouldn't do anything. There are no errors or pop-ups; it just doesn't go anywhere.
Next, I would hit cancel and have it call me, but then the GTM app disappears. Even after I was able to finally sign in, the app never opened up. The only way to get it to work was to end the meeting after I had signed in and start a new one.
@CABryant From your Add or remove programs section, uninstall anything there related to "GoTo".
Once completely removed, you can log into your GoToMeeting account online and host an impromptu meeting to update the software on your Windows 10 OS.