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Warning Cannot Modify Header Information - Headers Already Sent By (output Started At /home/content
up Warning: Cannot modify header information - headers already sent by ERROR [duplicate] up vote 62 down vote favorite 40 Possible Duplicate: Headers already sent by PHP I've been struggling with this error for a while now. To start with, I just thought it was white space, but after further research I think it might be a problem similar to this: Look for warning cannot modify header information wordpress any statements that could send output to the user before this header statement. If you find one or more, change your code to move the header statement before them. Complex conditional statements may complicate the issue, but they may also help solve the problem. Consider a conditional expression at the top of the PHP script that determines the header value as early as possible and sets it there. I'm guessing the include header is causing the problem along with the header(), but I'm not sure how to rearrange the code to get rid of this error. How do I remove the error?
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be within your files. You could have unknowingly created them when you are modifying WordPress or your Theme files. You will see something similar to the following error message. Warning: Cannot modify header information cannot modify header information - headers already sent by opencart - Header already sent by (Output started at /blog/wp-config.php:34) Locating the error We can
Header("location: $location", True, $status);
troubleshoot this issue by looking at the file which the error message is pointing to. Looking at the above sample error,
Php Redirect Without Header
we can see that it points towp-config.php. This error usually happens inwp-config.php orfunctions.php, because both files are most frequently edited by users. If you happen to be editing a theme file other than functions.php, http://stackoverflow.com/questions/9707693/warning-cannot-modify-header-information-headers-already-sent-by-error then it's highly possible that the error is from the file that you have just edited. Therefore, it's always good practice to keep a list of files that you have worked on. In programming, we call this file a changelog. Troubleshooting You will need to use yourFTP program to edit the file on your server. Use your FTP program to login to your web server. Navigate to your http://docs.presscustomizr.com/article/196-warning-cannot-modify-header-information-header-already-sent-by file, in the example, it's the wp-config.php. Open up wp-config.php file. Look for sign at the end of the file, it there is any, you will need to remove any empty space after it. If you cannot find any ?> sign at the end of the file, you will not need to do anything. Just to play safe, you can remove empty lines. If your error points to functions.php, you can carry out the same procedure. Error caused by plugin If you are unable to locate the error, and unable to fix it. There is a high chance that it's coming from a plugin. You can disable all plugins to see if it fixes your issue. If indeed it's cause by a plugin, you can start finding it by enabling one plugin at a time, and re-loading your website. After you have found the plugin that's causing this issue, you will need to disable it and report this issue to the plugin developer. External Resources H
class="nx">modify headerinformation-headersalreadysentby... And you have no idea what it means and/or how to fix it, this article is for http://markonphp.com/warning-cannot-modify-header-information-headers-already-sent-by you! You can either go straight to the fix OR read everything to https://www.arclab.com/en/kb/php/php-warning-cannot-modify-header-information-headers-already-sent.html understand exactly what is happening. What is the "Header" in the Message? In the warning message, you can see that your PHP code “already sent the headers”. So, what are those headers and why are they “already sent”? And why is it a problem anyway?! The “headers” in question are the HTTP headers. See, when already sent your browser issues a request on a page, like if you would browse to http://www.yoursite.com/a-page.php, the server answering your request will send back a response containing the resulting HTML. The server is the computer where the PHP code will be read and executed, by the way. Here’s a simple example: If you need to know more about how requests work from your browser to a server, you can read cannot modify header my article Server Side VS Client Side. Anyhow, the response that the server sends back to your browser is made of the body containing the HTML, but also the headers containing other information (like cookies and other useful information to your browser). If you’re curious, here’s what an HTTP response could look like: Everything before the is the header. After the header, there’s the body of the response which, in this case, contains the HTML of the requested page. But, here’s the thing: by default, PHP won’t wait until all of your code is executed before starting to send back the response. It will send it by chunk. It was made like this probably to save resources (memory) and people online still argue if it’s really more efficient or not. Nevertheless, this is how PHP behave if the output buffering is set to “false”. And, of course since PHP has to send the header first before any HTML content, it will send the header before any “chunk”. So, it sends the first chunk with the header, and if your code tries to modify the header afterward, this “warning” will be raised. How is the "Header Modified"? So, PHP sends the HTTP header a
Arclab on Twitter Arclab on Google+ German Website Cookies & Privacy php Warning: Cannot modify header information - headers already sent Echo before header Solution: RemoveRemove the echo before headerUse ob_start(); and ob_end_flush(); for buffered output New-line characters or spaces before Solution: Remove everything before Solution: Change the file encoding to "without BOM" (e.g. using notepad++) or remove the BOM before ...