Title: call_user_func_array()   Cannot modify header information
Last modified: August 22, 2016

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# call_user_func_array() Cannot modify header information

 *  [SRD75](https://wordpress.org/support/users/srd75/)
 * (@srd75)
 * [11 years, 3 months ago](https://wordpress.org/support/topic/call_user_func_array-cannot-modify-header-information/)
 * Running a WordPress 4.1 network in subdir mode. No errors in network admin, but
   in child site admin, I receive the following errors:
 *     ```
       Warning: call_user_func_array() expects parameter 1 to be a valid callback, function 'add_admin_scripts' not found or invalid function name in /.../public_html/test/wp-includes/plugin.php on line 496
   
       Warning: Cannot modify header information - headers already sent by (output started at /.../public_html/test/wp-includes/plugin.php:496) in /.../public_html/test/wp-includes/option.php on line 748
   
       Warning: Cannot modify header information - headers already sent by (output started at /.../public_html/test/wp-includes/plugin.php:496) in /.../public_html/test/wp-includes/option.php on line 749
       ```
   

Viewing 1 replies (of 1 total)

 *  Thread Starter [SRD75](https://wordpress.org/support/users/srd75/)
 * (@srd75)
 * [11 years, 3 months ago](https://wordpress.org/support/topic/call_user_func_array-cannot-modify-header-information/#post-5744520)
 * /wp-admin/error_log contains multiple instances of the following:
 *     ```
       [03-Feb-2015 04:30:52 UTC] PHP Warning:  call_user_func_array() expects parameter 1 to be a valid callback, function 'add_admin_scripts' not found or invalid function name in /.../public_html/test/wp-includes/plugin.php on line 496
       [03-Feb-2015 04:30:52 UTC] PHP Warning:  Cannot modify header information - headers already sent by (output started at /.../public_html/test/wp-includes/plugin.php:496) in /.../public_html/test/wp-includes/option.php on line 748
       [03-Feb-2015 04:30:52 UTC] PHP Warning:  Cannot modify header information - headers already sent by (output started at /.../public_html/test/wp-includes/plugin.php:496) in /.../public_html/test/wp-includes/option.php on line 749
       ```
   

Viewing 1 replies (of 1 total)

The topic ‘call_user_func_array() Cannot modify header information’ is closed to
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## Tags

 * [Cannot modify header information](https://wordpress.org/support/topic-tag/cannot-modify-header-information/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 1 reply
 * 1 participant
 * Last reply from: [SRD75](https://wordpress.org/support/users/srd75/)
 * Last activity: [11 years, 3 months ago](https://wordpress.org/support/topic/call_user_func_array-cannot-modify-header-information/#post-5744520)
 * Status: not resolved

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