note 51806 deleted from function.header by betz

Note Submitter: baktec at gmail dot com ---- I'm planning to do a simple authentication. I want to redirect the page to another php page file if the user name and password is correct. But. I'm having a problem with the header(). HERE is the part of my code that is showing the error. <body> <?php if ($p = $u) { header("Location:1.php"); //I'm getting the error below /*Warning: Cannot modify header information - headers already sent by (output started at C:\WebRoot\mySite\auth.php:3) in C:\WebRoot\mySite\auth.php on line 4*/ exit; } ?> </body> How can i solve this problem?