Title: Error messages while using this plugin
Last modified: August 21, 2016

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# Error messages while using this plugin

 *  [richard_vermeer](https://wordpress.org/support/users/richard_vermeer/)
 * (@richard_vermeer)
 * [11 years, 10 months ago](https://wordpress.org/support/topic/error-messages-while-using-this-plugin/)
 * Hi There,
 * Love the plugin, nice and easy solution to create an image map.
 * Unfortunately I am receiving the following warning messages while trying to create
   an image map:
 * Warning: call_user_func_array() expects parameter 1 to be a valid callback, function‘
   image-mapper’ not found or invalid function name in /home/xxxxxx/domains/mastbos-
   parelvanbreda.nl/public_html/wp-includes/plugin.php on line 470
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/xxxxx/domains/mastbos-parelvanbreda.nl/public_html/wp-includes/plugin.
   php:470) in /home/xxxx/domains/mastbos-parelvanbreda.nl/public_html/wp-admin/
   post.php on line 235
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/xxxx/domains/mastbos-parelvanbreda.nl/public_html/wp-includes/plugin.
   php:470) in /home/xxxx/domains/mastbos-parelvanbreda.nl/public_html/wp-includes/
   pluggable.php on line 1121
 * Can you help me out with this?
 * Thank you.
 * BR,
 * Richard
 * [https://wordpress.org/plugins/imagemapper/](https://wordpress.org/plugins/imagemapper/)

The topic ‘Error messages while using this plugin’ is closed to new replies.

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## Tags

 * [image map](https://wordpress.org/support/topic-tag/image-map/)
 * [warning](https://wordpress.org/support/topic-tag/warning/)

 * 0 replies
 * 1 participant
 * Last reply from: [richard_vermeer](https://wordpress.org/support/users/richard_vermeer/)
 * Last activity: [11 years, 10 months ago](https://wordpress.org/support/topic/error-messages-while-using-this-plugin/)
 * Status: not resolved