Hi All, I am using sendmail via php mail function to send emails. However few servers reject my mails with the error 'Sender address rejected: Domain not found', since mails from my server are sent as email at localhost.localdomain. How do I change this to a valid domain name ? We only own a public IP. we dont really have a domain name, is it possible to use IP ? Regards Deepan Facebook Sudoku Solver: http://apps.facebook.com/sudokusolver/ Sudoku Solver: http://www.sudoku-solver.net/ Home Page: http://www.codeshepherd/