Title: plugin.php error on upgrade to WP 2.6
Last modified: August 19, 2016

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# plugin.php error on upgrade to WP 2.6

 *  Resolved [greenpeas](https://wordpress.org/support/users/greenpeas/)
 * (@greenpeas)
 * [17 years, 11 months ago](https://wordpress.org/support/topic/pluginphp-error-on-upgrade-to-wp-26/)
 * Warning: call_user_func_array() [function.call-user-func-array]: First argumented
   is expected to be a valid callback, ‘version_warning’ was given in /homepages/
   40/d154139219/htdocs/clifton/wp-includes/plugin.php on line 311

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

 *  [marcoferreira2k8](https://wordpress.org/support/users/marcoferreira2k8/)
 * (@marcoferreira2k8)
 * [17 years, 11 months ago](https://wordpress.org/support/topic/pluginphp-error-on-upgrade-to-wp-26/#post-808836)
 * i have the same error, anyone help us?
 *  [marcoferreira2k8](https://wordpress.org/support/users/marcoferreira2k8/)
 * (@marcoferreira2k8)
 * [17 years, 11 months ago](https://wordpress.org/support/topic/pluginphp-error-on-upgrade-to-wp-26/#post-808890)
 * problem fixed it was caused because a plugin:
    [http://gadgets.blogs2k.com/2008/07/15/wordpress-26-plugins-problem/](http://gadgets.blogs2k.com/2008/07/15/wordpress-26-plugins-problem/)
 *  Thread Starter [greenpeas](https://wordpress.org/support/users/greenpeas/)
 * (@greenpeas)
 * [17 years, 10 months ago](https://wordpress.org/support/topic/pluginphp-error-on-upgrade-to-wp-26/#post-809277)
 * Thanks, this was most certainly a fix for me!

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

The topic ‘plugin.php error on upgrade to WP 2.6’ is closed to new replies.

## Tags

 * [plugins.php](https://wordpress.org/support/topic-tag/plugins-php/)
 * [upgrade](https://wordpress.org/support/topic-tag/upgrade/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 3 replies
 * 2 participants
 * Last reply from: [greenpeas](https://wordpress.org/support/users/greenpeas/)
 * Last activity: [17 years, 10 months ago](https://wordpress.org/support/topic/pluginphp-error-on-upgrade-to-wp-26/#post-809277)
 * Status: resolved

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