Cannot modify header information error - Tried everything I could find

Question

I've read 4 or 5 different threads about this so far, but after trying the suggestions, I can't figure this out.

I'm just trying to set a cookie, but on 3 of 5 pages the "Cannot modify" error is showing up. My page still loads though.

This code is in an include on all pages, and it loads before the html on all pages. (it's included in my header.php file, which is on all pages.)

<?php
if (!isset($_COOKIE['loggedinGaArms'])){
    header("location:index.php");
    exit();
}
else{
    $seconds = 2628000 + time();
    setcookie(loggedinGaArms, date("F js - g:i a"), $seconds);
}
/**
 * Check Logged-in Status via Cookie
 */
?>

My Header.php file (just the first few lines)

<?php
include_once "cookieset.php";/******** SET COOKIE INCLUDE ***/
$page = basename($_SERVER['PHP_SELF']);
?>
<!doctype html><!-------------- FIRST LINE OF HTML ----------->
<html>
<head>
    <meta name="robots" content="noindex">
    <meta charset="UTF-8">
    <title>Georgia Arms Inventory</title>
    <link rel="stylesheet" type="text/css" href="_/style.css">
    <script type="text/javascript" src="_/custom.js"></script>
</head>
<body>
    <!--  Start Main Content  -->
    <div id="content">

Both my database and html are UTF-8.

try to remove these designed comments from your code and use simple `//SET COOKIE INCLUDE` — Rohitashv Singhal, Sep 14 '13 at 06:10
I added those comments for posting here. I've tried removing the other comments though. — Jacques ジャック, Sep 14 '13 at 06:13
Notice: Use of undefined constant loggedinGaArms - assumed 'loggedinGaArms' is what is returned when I added the error reporting. — Jacques ジャック, Sep 14 '13 at 06:14
Do you see a non-quoted string? Literally all of the code in that file (aside from the comments) are posted above. — Jacques ジャック, Sep 14 '13 at 06:19
There are only two occurrences of "loggedinGaArms", one of which isn't quoted... — deceze, Sep 14 '13 at 06:20
That did not remove the error, but it did remove the "Notice" — Jacques ジャック, Sep 14 '13 at 06:23
So, have you tried **everything** from that other answer linked above? — deceze, Sep 14 '13 at 06:26
@deceze I have removed all white space, the file is being called before the HTML, it's only happening on 3 of the 5 pages with the file being linked. Etc. I've done everything on that that applies as far as I can tell. Also, I'm not sure how to check the Byte Order Thing. — Jacques ジャック, Sep 14 '13 at 06:32
@deceze I also just tried making it on one line, no carriage returns. The cookie is being set on line one. Still have the error. — Jacques ジャック, Sep 14 '13 at 06:35

score 2 · Accepted Answer · answered Sep 14 '13 at 06:14

2

Given that you has explicitly stated that your are encoding your files as UTF-8 what you may be seeing is the results of having a BOM (byte order mark) at the beginning of your PHP document. This constitutes output to the browser that is generally invisible in an IDE but will cause the failure that you are seeing.

Other helpful tips are to drop the tailing ?> mark from any PHP file that only contains code. It is unnecessary and opens the door for hard to detect white-space to exist after it.

With error reporting turned on the error should give a pretty clear indication of where output was started that caused the header call to fail, so I would suggest cranking up error reporting to see where the true problem actually lies.

answered Sep 14 '13 at 06:14

Orangepill

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`error_reporting(E_ALL); ini_set("display_errors", 1);` is on, it returns: Notice: Use of undefined constant loggedinGaArms - assumed 'loggedinGaArms' – Jacques ジャック Sep 14 '13 at 06:16
@Jack Probably won't fix the original quertion but you should put quotes around the `loggedinGaArms` in the setcookie call. – Orangepill Sep 14 '13 at 06:20
I just did that and the "Notice: Use of..." is not being returned anymore. But it's still showing the other error. – Jacques ジャック Sep 14 '13 at 06:21
@Jack did you check for the byte order mark? Let me know what editor you use and I may be able to direct you on how to confirm if it is there or not. – Orangepill Sep 14 '13 at 06:22
How do I check for that? Here is a link to source view-source:http://lucienconsulting.com/Georgia-Arms/categories.php – Jacques ジャック Sep 14 '13 at 06:24
The error message is indicating the the output is being started at the first character of the categories.php file. If you can confirm that there is no visible characters before the ` – Orangepill Sep 14 '13 at 06:35
Great, so now I know what the problem is :D Mind telling me how to fix? Or have a link? – Jacques ジャック Sep 14 '13 at 06:41
@Jack In your editor there should be an option to save without the BOM. Let me know what editor you use and I may be able to give more direction. – Orangepill Sep 14 '13 at 06:43
Im using Sublime Text 2 – Jacques ジャック Sep 14 '13 at 06:44
Found an option that says "Save With Encoding > UTF 8" right above UTF 8 BOM, so I assume that will do it. – Jacques ジャック Sep 14 '13 at 06:46

score 1 · Answer 2 · answered Sep 14 '13 at 06:03

1

The error Cannot modify header information - headers already sent error means that you echo content before you modify the headers. The data that is sent before this error occurs should appear on the web page before the error is printed. The error is fixed if you move the setcookie() function before that content.

answered Sep 14 '13 at 06:03

Sumurai8

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I appreciate the answer, but the `setcookie()` comes before everything that's not php. It's inside an `if` statement. But as you can see from the code I posted, the file is included before the `` tag. – Jacques ジャック Sep 14 '13 at 06:06
Look at the actual html it outputs, not the php file. (e.g. `view-source:http://www.yoursite.com/yourpage`). There is simply no other case where this error boils up. – Sumurai8 Sep 14 '13 at 06:08
This is what was retured after the PHP error statements ` Georgia Arms Inventory

Georgia Arms

Add New Product

`
– Jacques ジャック Sep 14 '13 at 06:15
I agree that there is no other case, but I'm reusing code that works on 3 other sites for this :/ It's very frustrating and I've been researching and trying to fix this for 4 hours. – Jacques ジャック Sep 14 '13 at 06:17
It is only relevant what is returned before that error statement. The error is printed as soon as php reaches the `setcookie()` function. Anything that is printed before that error is causing the error to appear. What @Orangepill says is true: You could simply be printing whitespace/newlines outside php tags. – Sumurai8 Sep 14 '13 at 06:21
view-source:http://lucienconsulting.com/Georgia-Arms/categories.php – Jacques ジャック Sep 14 '13 at 06:21
What is on line 1 of `categories.php`? Notepad displays a space before the error, so I assume you have a space somewhere there. – Sumurai8 Sep 14 '13 at 06:37
There was a space there. There is not anymore, and it's still throwing the error. – Jacques ジャック Sep 14 '13 at 06:40
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/37379/discussion-between-sumurai8-and-jack) – Sumurai8 Sep 14 '13 at 06:48

score 0 · Answer 3 · answered Sep 14 '13 at 06:04

0

It could be an issue with the file you are including, or any other files that are being used.

Make sure that such files do not have a PHP closing tag ?> at the end (that is, if they only perform logic, and do not output any HTML.

Make sure that there are no accidental spaces before the opening tags <?php on any of the files.

Otherwise, consider using ob_start and ob_get_clean: http://php.net/manual/en/function.ob-start.php

answered Sep 14 '13 at 06:04

Mike Rockétt

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I tried removing the closing php tag, but it did not change anything. The odd thing is that it is not throwing the error on 2 of the pages. – Jacques ジャック Sep 14 '13 at 06:09

score 0 · Answer 4 · answered Sep 14 '13 at 06:09

Generally this issue is generated whenever you have a lot of blank spaces or comments in your php file or you may not have end ?> php tag. check this that is there any blank space before opening <?php.

Besides this you may also use ob_start at the start of your php file.

You may take help of

http://php.net/manual/en/function.ob-start.php

Cannot modify header information error - Tried everything I could find

4 Answers4