Short answer
Your script tried to send a header — a redirect, a cookie — after output had already started. The usual culprit is a blank line or a stray space before the opening
<?php tag in an included file. The error message names the file and line that produced the output.Learn more
- “Cannot modify header information - headers already sent”Fix the PHP headers already sent warning: stray whitespace, byte order marks and output before redirects or cookies.
- Understanding PHP error messagesHow to read a PHP error: fatal errors, parse errors, warnings, notices and deprecations, what each means for your site, and where to look next.
- How to find PHP errors (error logs and display_errors)Where PHP errors are recorded on Traxio, how to log errors without showing them to visitors, and how to set up logging for a custom application.
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