my problem is this..,
After admin or the particular user press update button in edit user page or in the profile page, I have to validate the email address whether that particular email address already available in a table which I have defined. If that email address is already available in that table, I have to rollback the updated email address in the wordpress user table and show an error message. I have tried with 'pre_user_email' hook, but if modified the $_REQUEST['email'] then it update as blank field in the database. and shows an empty email address in profile and edit user page.
Please help on this..