Warning: call_user_func_array() expects parameter 1 to be a valid callback.

  • Hello,

    I searched tons of posts about this but can’t find a solution.

    Warning: call_user_func_array() expects parameter 1 to be a valid callback, array must have exactly two members in /home/account/public_html/ksenia.se/wp-includes/class-wp-hook.php on line 286

    The health control says “A plugin has prevented updates by disabling wp_version_check()”

    I have disabled all plugins/adons and deactivated my theme and set it to the default Twenty Nineteen and i still get this warning.

    The site works without problem but i’d like to clean this warning thingy.

    Cheers / Johny

    The page I need help with: [log in to see the link]

Viewing 3 replies - 1 through 3 (of 3 total)
  • Moderator bcworkz

    (@bcworkz)

    If you have no plugins active and are using the twentynineteen theme and you still get the prevented updates warning, that tells me you are using a WP installation provided by your host who has assumed update responsibility. That’s fine in general, except they probably have modified their version of WP which causes the PHP warning.

    To find out the exact cause of the warning, we need a backtrace of the error. Does your error log include such data? If not, try defining WP_DEBUG as true in wp-config.php. The warning that shows up on your site might include a backtrace. It depends on your PHP configuration. If not, you could temporarily install a custom error handler into the active theme’s functions.php, like the one listed here.

    Restore WP_DEBUG to false to prevent warnings from being listed on your site.

    Thread Starter jakerlund

    (@jakerlund)

    Thanks bcwokz,

    I didn’t know about the wp_debug mode.
    Now i can see it’s the “MinervaKB Knowledge Base” plugin.
    I’ve sent a message to the developer but it seems i have to renew my support for $56 to be allowed posting in the normal comment section. ??

    This is what came up with the wp_debug set to true.

    Deprecated: strpos(): Non-string needles will be interpreted as strings in the future. Use an explicit chr() call to preserve the current behavior in /home/account/public_html/ksenia.se/wp-content/plugins/minervakb/lib/vendor/plugin-update-checker/Puc/v4p4/Plugin/UpdateChecker.php on line 641

    • This reply was modified 5 years, 2 months ago by jakerlund.
    Moderator bcworkz

    (@bcworkz)

    That strpos() bit would not cause the valid callback warning. The strpos() bit is something the plugin devs should address, but what they are currently doing is probably OK for now. Apparently you are not getting a backtrace by default. One is needed to figure out the source of the valid callback warning. Install the code I linked previously into functions.php of the active theme. Leave WP_DEBUG set to true for now.

    Do whatever action generated the valid callback warning. With the linked code in place, the warning will be followed by several lines noting the path followed to get to the point where the warning was triggered. Post all the backtrace output here and hopefully we can deduce the source of the problem.

    Once you get the backtrace information, you can restore WP_DEBUG to false. Leaving it as true for a long time slightly decreases the security of your site.

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