We have recently added an option to login/sign up with GRE Prep Club using a LinkedIn login.
We created a widget called "GRE Prep Club Authenticate" that allows you to authenticate/login to the GRE Prep Club forum using your existing LinkedIn credentials. In this case, none of your email/password information on LinkedIn is being passed on to GRE Prep Club. However, when you sign up, LinkedIn does transmit to GRE Prep Club your email address from LinkedIn as well as a link to your profile. LinkedIn also shares your other basic information such as name, headline, and current positions - we do not use that information nor do we display it on the site; thus using the LinkedIn login option will keep your experience and privacy on GRE Prep Club the same as it would have been using just email and password. The login with LinkedIn is simply a convenience of not having to have another password.
If you would like to decouple your LinkedIn account from the profile, you can simply request a password by using the "Forgot Password Link" at login. The system will generate a password that will be emailed to you and then you can login using a standard method - username/email and password.
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