invalid credential error -google userinfo api
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I am trying to fetch the email-address of the user through the Google UserInfo API "https://sites.google.com/site/oauthgoog/Home/emaildisplayscope"


I am using a valid access token but am still getting the invalid crdetial error.
My app is implementing Oauth 1.0 Is it possible that the API requires Oauth 2 token.
If yes,what is the other way to get the email address of a user?