How can the issue of "Cannot modify header information" errors in PHP scripts be prevented or fixed?

The "Cannot modify header information" error in PHP scripts occurs when there is an attempt to change header information after it has already been sent to the browser. To prevent this error, make sure to set any header information before sending any output to the browser, such as HTML content or whitespace. 

<?php
ob_start(); // Start output buffering

// Set header information before any output
header('Content-Type: text/html');

// Your PHP code here

ob_end_flush(); // Flush output buffer
?>

Keywords

header output buffering ob_start ob_end_flush ob_clean

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