Title: Theme Switcher plugin problems
Last modified: August 18, 2016

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# Theme Switcher plugin problems

 *  Resolved [rissie](https://wordpress.org/support/users/rissie/)
 * (@rissie)
 * [20 years, 11 months ago](https://wordpress.org/support/topic/theme-switcher-plugin-problems/)
 * So I was using this theme switcher: [http://dev.wp-plugins.org/wiki/ThemeSwitcher](http://dev.wp-plugins.org/wiki/ThemeSwitcher)
 * And all was well until I activated it, and suddenly, this error was scrawled 
   across the top of my admin page:
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/.madam/rissie/rissie.net/wordpress/wp-content/plugins/theme-switcher.
   php:164) in /home/.madam/rissie/rissie.net/wordpress/wp-admin/admin.php on line
   6
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/.madam/rissie/rissie.net/wordpress/wp-content/plugins/theme-switcher.
   php:164) in /home/.madam/rissie/rissie.net/wordpress/wp-admin/admin.php on line
   7
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/.madam/rissie/rissie.net/wordpress/wp-content/plugins/theme-switcher.
   php:164) in /home/.madam/rissie/rissie.net/wordpress/wp-admin/admin.php on line
   8
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/.madam/rissie/rissie.net/wordpress/wp-content/plugins/theme-switcher.
   php:164) in /home/.madam/rissie/rissie.net/wordpress/wp-admin/admin.php on line
   9
 * doesn’t effect my site in any way, but when I deactivate the plugin, all that
   goes away. I have no idea what that means. Any ideas?

Viewing 4 replies - 1 through 4 (of 4 total)

 *  [moshu](https://wordpress.org/support/users/moshu/)
 * (@moshu)
 * [20 years, 11 months ago](https://wordpress.org/support/topic/theme-switcher-plugin-problems/#post-233828)
 * This might be helpful:
    [http://codex.wordpress.org/Answers-Trouble_Shooting#Headers_already_sent](http://codex.wordpress.org/Answers-Trouble_Shooting#Headers_already_sent)
 *  Thread Starter [rissie](https://wordpress.org/support/users/rissie/)
 * (@rissie)
 * [20 years, 11 months ago](https://wordpress.org/support/topic/theme-switcher-plugin-problems/#post-233832)
 * Not really, ’cause everything works fine once I deactivate the theme switcher..
   the theme switcher itself is doing something, and I went through it, and there
   doesn’t seem to be anything like described wrong with it.
 * Thanks for trying.
 *  Thread Starter [rissie](https://wordpress.org/support/users/rissie/)
 * (@rissie)
 * [20 years, 11 months ago](https://wordpress.org/support/topic/theme-switcher-plugin-problems/#post-233834)
 * You know, now that I give it a second look, that did work. I double-checked and
   I had extra space tacked on to the end of the theme switcher file. So thanks 
   for the help =)
 *  [Beel](https://wordpress.org/support/users/beel/)
 * (@beel)
 * [20 years, 11 months ago](https://wordpress.org/support/topic/theme-switcher-plugin-problems/#post-233835)
 * I have theme-switcher installed (and a lot of other plugins). Any time I have
   had that error message it was because of extra “whitespace” somewhere in one 
   of the files.
 * Edit: Glad you got it. Also, for future reference the extra whitespace in plugins
   can cause your rss to fail even when it does not give the header error message.

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘Theme Switcher plugin problems’ is closed to new replies.

 * 4 replies
 * 3 participants
 * Last reply from: [Beel](https://wordpress.org/support/users/beel/)
 * Last activity: [20 years, 11 months ago](https://wordpress.org/support/topic/theme-switcher-plugin-problems/#post-233835)
 * Status: resolved

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