I had this issue last week. However, I haven't logged into any infotainment services up until that point (picked up car on 12/30). When I tried to log into youtube with my own account I got the current error that the browser isn't secure or something. I browsed to the plex.tv site, used my google account to log in successfully, then loaded up YouTube and saw it was logged into my account. Also browsed to gmail.com and it opened my emails for that account automatically. The only thing different from others here is that nothing was ever logged in using my google account to start with until I logged into plex.tv (never used plex.tv before either). Is there a clear cache or log out of all accounts option - then try to login again?