Title: error – wp-includes/plugin.php on line 173
Last modified: August 20, 2016

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# error – wp-includes/plugin.php on line 173

 *  Resolved [magcrew](https://wordpress.org/support/users/magcrew/)
 * (@magcrew)
 * [13 years, 5 months ago](https://wordpress.org/support/topic/error-wp-includespluginphp-on-line-173/)
 * im not sure what i did to make this happen and that is making it difficult for
   me to fix.
 * im having an error on every page i post now and it reads
 * Warning: call_user_func_array() [function.call-user-func-array]: First argument
   is expected to be a valid callback, ” was given in /home/username/public_html/
   wp-includes/plugin.php on line 173
 * any input would be appreciated.
 * thanks

Viewing 3 replies - 1 through 3 (of 3 total)

 *  [David100351](https://wordpress.org/support/users/david100351/)
 * (@david100351)
 * [13 years, 5 months ago](https://wordpress.org/support/topic/error-wp-includespluginphp-on-line-173/#post-3314573)
 * This appeared today when I installed bestwebsoft’s captcha. [http://wordpress.org/extend/plugins/captcha/](http://wordpress.org/extend/plugins/captcha/)
   on an existing working setup. It went when I deleted it.
 * I think (based on what happens on my other sites) that it doesn’t mix with User
   Spam Remover. [http://wordpress.org/extend/plugins/user-spam-remover/](http://wordpress.org/extend/plugins/user-spam-remover/).
   Sites which don’t have that on, don’t have the problem.
 * But it could be another plugin: it’s just that seems the most likely.
 * If you agree that’s the likely cause would you put a link in the appropriate 
   place!
 *  Thread Starter [magcrew](https://wordpress.org/support/users/magcrew/)
 * (@magcrew)
 * [13 years, 5 months ago](https://wordpress.org/support/topic/error-wp-includespluginphp-on-line-173/#post-3314576)
 * i installed the same plugin yesterday and deleted it, and thats what it was.
 * what do you mean by putting a link in the appropriate place? you lost me on that.
 * thanks for the reply.
 *  [David100351](https://wordpress.org/support/users/david100351/)
 * (@david100351)
 * [13 years, 5 months ago](https://wordpress.org/support/topic/error-wp-includespluginphp-on-line-173/#post-3314584)
 * NP.
 * I meant on the captcha support forum (if that was what it was).
 * I’ll do it, linking to this.

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘error – wp-includes/plugin.php on line 173’ is closed to new replies.

 * 3 replies
 * 2 participants
 * Last reply from: [David100351](https://wordpress.org/support/users/david100351/)
 * Last activity: [13 years, 5 months ago](https://wordpress.org/support/topic/error-wp-includespluginphp-on-line-173/#post-3314584)
 * Status: resolved

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