hi how to authenticate asp page

 hi,
i am using login control , but my problem is i can't redirect to target page

if ((UserEmail.Text == "BBB") &&
            (UserPass.Text == "AAA"))
        {
            FormsAuthentication.RedirectFromLoginPage
               (UserEmail.Text, Persist.Checked);
           
        }
        else
        {
            Msg.Text = "Invalid credentials. Please try again.";
        }

...