Title: Warning: call_user_func() expects parameter 1 to be a valid callback, function ‘
Last modified: April 3, 2017

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# Warning: call_user_func() expects parameter 1 to be a valid callback, function ‘

 *  [yab1986](https://wordpress.org/support/users/yab1986/)
 * (@yab1986)
 * [9 years, 2 months ago](https://wordpress.org/support/topic/warning-call_user_func-expects-parameter-1-to-be-a-valid-callback-function/)
 * Hi there
 * In the “Edit Staff Member” area I get following message in the Staff Photo section:
   
   Warning: call_user_func() expects parameter 1 to be a valid callback, function‘
   sslp_staff_member_warning_meta_box’ not found or invalid function name in /home/
   tst/www/mypage.ch/wp-admin/includes/template.php on line 1048
 * Is there any fix or hotfix which I can do?
 * Many thanks for supporting.
 * Best regards,
    Yab1986

The topic ‘Warning: call_user_func() expects parameter 1 to be a valid callback,
function ‘’ is closed to new replies.

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## Tags

 * [staff-members](https://wordpress.org/support/topic-tag/staff-members/)

 * 0 replies
 * 1 participant
 * Last reply from: [yab1986](https://wordpress.org/support/users/yab1986/)
 * Last activity: [9 years, 2 months ago](https://wordpress.org/support/topic/warning-call_user_func-expects-parameter-1-to-be-a-valid-callback-function/)
 * Status: not resolved