Title: Invalid argument / Cannot modify header information
Last modified: August 19, 2016

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# Invalid argument / Cannot modify header information

 *  [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * (@measuredrecords)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/)
 * Hi everyone…
    I hope you are well. I am a wordpress rookie, don’t know much about
   PHP at all so I am hoping that someone out there can be good enough to explain
   in simple terms what I need to do to fix the site I am administrating. I have
   spent a while googleing the problem but it seems there are multiple solutions.
 * My site is located at: [http://www.measuredrecords.com](http://www.measuredrecords.com)
   
   I haven’t made ANY updates or edits to the site in a while, but all of a sudden
   is it displaying the following error:
 *     ```
       Warning: Invalid argument supplied for foreach() in /home/measuredrecords/wordpress/wp-includes/classes.php on line 92
   
       Warning: Cannot modify header information - headers already sent by (output started at /home/measuredrecords/wordpress/wp-includes/classes.php:92) in /home/measuredrecords/wordpress/wp-includes/pluggable.php on line 391
       ```
   
 * Line 92 of the classes.pho file is:
 *  $request_match = $req_uri . ‘/’ . $request;
 * and line 391 of the pluggable.php file is:
 * header(“Location: $location”);
 * If someone would be kind enough to help me out with this problem, that would 
   be great. Please let me know if I can provide any further information.
 * Regards,
    Louise

Viewing 8 replies - 1 through 8 (of 8 total)

 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1037818)
 * Have you:
    1. installed or updated any plugins recently?
    2. activated a new theme?
    3. updated your existing theme?
    4. tried activating the default theme?
 *  Thread Starter [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * (@measuredrecords)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1037834)
 * Hi Esmi,
 * The answer to all of those questions is no. I haven’t made one change on any 
   themes / plugins etc for months.
 * The site currently uses the wordpress default theme anyway.
 * Should I install a new theme?
 * Thanks
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1037877)
 * Can you activate the default theme? I could have sworn I managed to get to the
   front page of your site a few minutes ago.
 *  Thread Starter [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * (@measuredrecords)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1037970)
 * Hi esmi,
 * I de-activated the theme, and then re-activated it… I can see the front page 
   however there is still the one error message at the top:
 * Warning: Invalid argument supplied for foreach() in /home/measuredrecords/wordpress/
   wp-includes/classes.php on line 92
 * Thanks for your help in this matter, its much appreciated
 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1038015)
 * Switch to the default theme, deactivate all plugins and let’s see what happens…
 *  Thread Starter [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * (@measuredrecords)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1038071)
 * Hi Esmi
    Been playing around with this for days… I’ve de-activated all the plug-
   ins and have switched it back to the default theme. Now its not changing anything
   at all? Any ideas Anyone?
 * Kind Regards,
    Louise
 *  Thread Starter [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * (@measuredrecords)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1038081)
 * Hey folks,
 * Does anyone have any ideas what could be causing the above error message?
 * Regards,
    Louise
 *  Thread Starter [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * (@measuredrecords)
 * [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1038083)
 * Hi all,
    I managed to get the site back up by upgrading my wordpress version.
   Hope this helps anyone in the future. Cheers.

Viewing 8 replies - 1 through 8 (of 8 total)

The topic ‘Invalid argument / Cannot modify header information’ is closed to new
replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 8 replies
 * 2 participants
 * Last reply from: [measuredrecords](https://wordpress.org/support/users/measuredrecords/)
 * Last activity: [17 years, 1 month ago](https://wordpress.org/support/topic/invalid-argument-cannot-modify-header-information/#post-1038083)
 * Status: not resolved

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