Title: Error messages when activating plugin
Last modified: August 21, 2016

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# Error messages when activating plugin

 *  Resolved [SieniMaagi](https://wordpress.org/support/users/sienimaagi/)
 * (@sienimaagi)
 * [12 years, 9 months ago](https://wordpress.org/support/topic/error-messages-when-activating-plugin/)
 * Hi,
 * I have a wordpress site I’m building for my team (football), it’s still early
   in development but every time I activate Team Rosters-plugin (similar thing happens
   when I try to add a new game with Game Schedule-plugin):
 * `Notice: Undefined index: use_gallery_links in /path/to/my/site/wp-content/plugins/
   team-rosters/includes/mstw-team-rosters-admin.php on line 1605 Notice: Undefined
   index: use_gallery_links in /path/to/my/site/wp-content/plugins/team-rosters/
   includes/mstw-team-rosters-admin.php on line 1606 Warning: Cannot modify header
   information - headers already sent by (output started at /path/to/my/site/dev/
   wp-content/plugins/team-rosters/includes/mstw-team-rosters-admin.php:1605) in/
   path/to/my/site/wp-includes/option.php on line 571 Warning: Cannot modify header
   information - headers already sent by (output started at /path/to/my/site/wp-
   content/plugins/team-rosters/includes/mstw-team-rosters-admin.php:1605) in /path/
   to/my/site/wp-includes/option.php on line 572`
 * I have CCTM installed (tried to deactivate it, helped 0) also some other non-
   content touching plugins (tried to deactivate all of them)
 * [http://wordpress.org/plugins/team-rosters/](http://wordpress.org/plugins/team-rosters/)

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

 *  Thread Starter [SieniMaagi](https://wordpress.org/support/users/sienimaagi/)
 * (@sienimaagi)
 * [12 years, 9 months ago](https://wordpress.org/support/topic/error-messages-when-activating-plugin/#post-4038723)
 * When I did a fresh installment of a US – version WordPress (was using finnish
   version earlier) it worked just fine but now as I tried to change back to finnish
   it went even crazier (no plugins other than your plugins at the moment)
 *  Plugin Author [Mark O’Donnell](https://wordpress.org/support/users/markodonnell/)
 * (@markodonnell)
 * [12 years, 9 months ago](https://wordpress.org/support/topic/error-messages-when-activating-plugin/#post-4038728)
 * Hi SieniMaagi,
    Yes, this is a common problem. PHP is throwing warnings for indices
   which are not defined, because they haven’t been used yet. Then you can sometimes
   end up with the dreading “headers already sent message”, which is not good. Not
   a big deal, after you run the admin and save the settings once, even without 
   changing them, they go away. In the meantime, just turn off WordPress debug. 
   Edit your wp-config.php file and change
 * `define('WP_DEBUG', false);` to `define('WP_DEBUG', true);`
 * Let me know how that works out.
 * -Mark
 *  Thread Starter [SieniMaagi](https://wordpress.org/support/users/sienimaagi/)
 * (@sienimaagi)
 * [12 years, 9 months ago](https://wordpress.org/support/topic/error-messages-when-activating-plugin/#post-4038780)
 * Thanks, it’s working now

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

The topic ‘Error messages when activating plugin’ is closed to new replies.

 * ![](https://ps.w.org/team-rosters/assets/icon-128x128.png?rev=1087838)
 * [Team Rosters](https://wordpress.org/plugins/team-rosters/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/team-rosters/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/team-rosters/)
 * [Active Topics](https://wordpress.org/support/plugin/team-rosters/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/team-rosters/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/team-rosters/reviews/)

 * 3 replies
 * 2 participants
 * Last reply from: [SieniMaagi](https://wordpress.org/support/users/sienimaagi/)
 * Last activity: [12 years, 9 months ago](https://wordpress.org/support/topic/error-messages-when-activating-plugin/#post-4038780)
 * Status: resolved