Title: Error after Upgrading
Last modified: August 19, 2016

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# Error after Upgrading

 *  [giankar](https://wordpress.org/support/users/giankar/)
 * (@giankar)
 * [16 years, 11 months ago](https://wordpress.org/support/topic/error-after-upgrading-3/)
 * I tried to upgrade manually to 2.8, and when I try to enter the admin panel I
   get this error:
 * **Fatal error: Call to undefined function _cleanup_header_comment() in /home/
   disegnio/public_html/wp-admin/includes/plugin.php on line 89**
 * Any ideas?
 * Thank you in advance

Viewing 1 replies (of 1 total)

 *  [esmi](https://wordpress.org/support/users/esmi/)
 * (@esmi)
 * [16 years, 11 months ago](https://wordpress.org/support/topic/error-after-upgrading-3/#post-1114595)
 * Try deactivating all plugins first:
 * [How to deactivate all plugins when not able to access the administrative menus](http://codex.wordpress.org/FAQ_Troubleshooting#How_to_deactivate_all_plugins_when_not_able_to_access_the_administrative_menus.3F)

Viewing 1 replies (of 1 total)

The topic ‘Error after Upgrading’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 1 reply
 * 2 participants
 * Last reply from: [esmi](https://wordpress.org/support/users/esmi/)
 * Last activity: [16 years, 11 months ago](https://wordpress.org/support/topic/error-after-upgrading-3/#post-1114595)
 * Status: not resolved

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