Title: Warning after activation plugin
Last modified: August 21, 2016

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# Warning after activation plugin

 *  Resolved [seraphinne](https://wordpress.org/support/users/seraphinne/)
 * (@seraphinne)
 * [13 years ago](https://wordpress.org/support/topic/warning-after-activation-plugin/)
 * Hello,
 * I want to let you know that when I installed and activated this plugin I got 
   to see the followin:
 * > Warning: Missing argument 1 for plugin_dir_url(), called in /public/sites/burogu.
   > avo-forum.nl/wp-content/plugins/gamma-gallery/gammagallery.php on line 13 and
   > defined in /public/sites/burogu.avo-forum.nl/wp-includes/plugin.php on line
   > 599
   > Warning: session_start() [function.session-start]: Cannot send session cache
   > limiter – headers already sent (output started at /public/sites/burogu.avo-
   > forum.nl/wp-includes/plugin.php:599) in /public/sites/burogu.avo-forum.nl/wp-
   > content/plugins/si-contact-form/si-contact-form.php on line 1997
 * > The plugin generated 274 characters of unexpected output during activation.
   > If you notice “headers already sent” messages, problems with syndication feeds
   > or other issues, try deactivating or removing this plugin.
 * I use the theme Esplanade.
 * [http://wordpress.org/extend/plugins/gamma-gallery/](http://wordpress.org/extend/plugins/gamma-gallery/)

Viewing 2 replies - 1 through 2 (of 2 total)

 *  [Kieran McCarthy](https://wordpress.org/support/users/youghalonline/)
 * (@youghalonline)
 * [13 years ago](https://wordpress.org/support/topic/warning-after-activation-plugin/#post-3668480)
 * Same errors after activating for me as above. Uninstalled it.
 *  Plugin Author [ezhil](https://wordpress.org/support/users/ezhil/)
 * (@ezhil)
 * [13 years ago](https://wordpress.org/support/topic/warning-after-activation-plugin/#post-3668497)
 * [@seraphinne](https://wordpress.org/support/users/seraphinne/), [@kieran](https://wordpress.org/support/users/kieran/)
   McCarthy
    hi, thanks for pointing out, the issue has been resolved in the latest
   version [1.1](http://wordpress.org/extend/plugins/gamma-gallery/) ,

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Warning after activation plugin’ is closed to new replies.

 * ![](https://s.w.org/plugins/geopattern-icon/gamma-gallery_96867f.svg)
 * [Gamma Gallery](https://wordpress.org/plugins/gamma-gallery/)
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 * [Active Topics](https://wordpress.org/support/plugin/gamma-gallery/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/gamma-gallery/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/gamma-gallery/reviews/)

 * 2 replies
 * 3 participants
 * Last reply from: [ezhil](https://wordpress.org/support/users/ezhil/)
 * Last activity: [13 years ago](https://wordpress.org/support/topic/warning-after-activation-plugin/#post-3668497)
 * Status: resolved