After I logged to facebook I am redirected on my forum but I have a blank page.

That's the redirect url after I logged into facebook :

http://myforum.com/auth.aspx?auth=facebook&code=AQDzCaQUVCrGPM3t_NJuTQk8yTLydSqUGquWxRTBEgam8I2o1m6ZxlNBGCmeSSzVLUFHCs2mxLHZKnNktZqO7uyfE-F9pcwT5m7Wb_Y02cEGYp_j6WGBng7USKQMJG7Ge5U6CL4aKFEzOa0bA5TwgE9ztRFoAWYzF2wiSM8HBXMhALIeNNFIBWz3TkuTqXEdxnIUht_OnR3CLhBFJ3L-s-mrPuVgjfd4SKgNlQbXtFBJdJ8Zvyl7mUZpvewzCtHOkYxRCf7XbO0w3nZSjAM8-o6UUTcaGPvkjfs4CcDTPkp4OSHYRn4OYivqT6uRZJbeX1g 

If I refresh the page I have a "Forum Error" message.

Error while trying to login or register the facebook user

System.ArgumentNullException: Value cannot be null.

Parameter name: Email cannot be null.

at YAF.Providers.Utils.ExceptionReporter.ThrowArgumentNull(String providerSection, String tag)

at YAF.Providers.Membership.YafMembershipProvider.GetUserNameByEmail(String email)

at YAF.Core.Services.Auth.Facebook.LoginOrCreateUser(HttpRequest request, String parameters, String& message)

at YAF.Auth.HandleFacebookReturn()

Thanks

in the next version there will be a warning message instead of the error screen.

Thanks

Yes the user can register normal without facebook.