Title: Error adding Plugin
Last modified: August 18, 2016

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# Error adding Plugin

 *  Resolved [victoriasarah](https://wordpress.org/support/users/victoriasarah/)
 * (@victoriasarah)
 * [20 years, 10 months ago](https://wordpress.org/support/topic/error-adding-plugin/)
 * Okay, so i tried to add the theme switcher plugin from here: [http://dev.wp-plugins.org/wiki/ThemeSwitcher](http://dev.wp-plugins.org/wiki/ThemeSwitcher)
   
   I did step by step but when it came to active the plugin this appeared:
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/heyloser/public_html/wp-content/plugins/theme-switcher.php:164) in /
   home/heyloser/public_html/wp-admin/admin.php on line 6
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/heyloser/public_html/wp-content/plugins/theme-switcher.php:164) in /
   home/heyloser/public_html/wp-admin/admin.php on line 7
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/heyloser/public_html/wp-content/plugins/theme-switcher.php:164) in /
   home/heyloser/public_html/wp-admin/admin.php on line 8
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/heyloser/public_html/wp-content/plugins/theme-switcher.php:164) in /
   home/heyloser/public_html/wp-admin/admin.php on line 9
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/heyloser/public_html/wp-content/plugins/theme-switcher.php:164) in /
   home/heyloser/public_html/wp-admin/plugins.php on line 21
 * How can i fix this?

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

 *  [Marc](https://wordpress.org/support/users/marc/)
 * (@marc)
 * [20 years, 10 months ago](https://wordpress.org/support/topic/error-adding-plugin/#post-225386)
 * You most likely have an extra space in the theme-switcher.php file.
 * Check to ensure there is no extra spaces either before <php? at the beginning
   of the plugin file or after the closing ?> tag.
 *  Thread Starter [victoriasarah](https://wordpress.org/support/users/victoriasarah/)
 * (@victoriasarah)
 * [20 years, 10 months ago](https://wordpress.org/support/topic/error-adding-plugin/#post-225388)
 * Thanks. That made it.

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

The topic ‘Error adding Plugin’ is closed to new replies.

 * 2 replies
 * 2 participants
 * Last reply from: [victoriasarah](https://wordpress.org/support/users/victoriasarah/)
 * Last activity: [20 years, 10 months ago](https://wordpress.org/support/topic/error-adding-plugin/#post-225388)
 * Status: resolved

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