Use Google Refresh token to access user information without authenticating user each time I have created a simple project which does following things: • When we want to get user data/information from Google • We don't want to authenticate user each time. • So, I have created a sample example, using C# MVC, Javascript project. • If you want to use it, First register your app in google console and get client id and secret id. • Fill client id and secret id variables in HomeController.cs page. • Now, If you run it for the first time it will ask you to authenticate from google and then it will import your Google contacts. I am saving refresh token obtain from authentication in file, but you can use database, file is only for example purpose. • Now, once I have refresh token second time if you want to get user contacts then it use that refresh token to get contact and user don’t need to authenticate. • There are many example in PHP but I was not able to find anything in C#.