Codeigniter header() error
NickName:Kevin Simper Ask DateTime:2011-09-14T05:34:41

Codeigniter header() error

I have run into this problem in my Codeigniter app:

A PHP Error was encountered
Severity: Warning
Message: Cannot modify header information - headers already sent by (output started at /application/controllers/training.php:1)
Filename: libraries/Session.php
Line Number: 671

I have been checking for whitespaces and I am not sending headers.

The ONLY way this error appears is when I am updating the view and controller files.

My code ran fine until I updated some files, then the error (above) refuses to disappear.

When I clear my cache and log back in again, the error doesn't show.

Does anyone know why?

Copyright Notice：Content Author:「Kevin Simper」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/7408827/codeigniter-header-error

Answers
Timur 2011-09-13T21:59:07

May be UTF-8 BOM marker? Try saving training.php without BOM (if exists)",

Cyclone 2011-09-13T21:39:46

I'm not sure why it would appear and disappear like that, but you're sending output in /application/controllers/training.php on line one, which means that any script run after that cannot modify the header. Essentially, something is invoking CI's session library in a way which is modifying the header, but the header's been sent. It'd be helpful if we could see line one of training.php.",

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