Title: Errors whenever activating plugins
Last modified: August 18, 2016

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# Errors whenever activating plugins

 *  Resolved [freddymungo](https://wordpress.org/support/users/freddymungo/)
 * (@freddymungo)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/)
 * I keep getting errors whenever I activate some of my plugins, which all say something
   like this:
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/website/public_html/wp-content/plugins/post-templates-by-cat.php:75)
   in /home/website/public_html/wp-admin/plugins.php on line 16
 * I have no idea how to fix it other than to not use any plugins. Any ideas?
 * Edit: Note that I mean, when I click the “activate” button, it takes me to a 
   page with that error message. If I go back one in my history, then the plugin
   is activated and everything’s dippy dandy– but that error message page makes 
   me a little uneasy. Should it?

Viewing 7 replies - 1 through 7 (of 7 total)

 *  [resiny](https://wordpress.org/support/users/resiny/)
 * (@resiny)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381372)
 * just a guess, try chmoding the theme files to 666
 *  [Mark (podz)](https://wordpress.org/support/users/podz/)
 * (@podz)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381397)
 * `post-templates-by-cat.php`
 * Download that.
    Scroll to the very bottom Put the cursor between the ? and the
   > Press Delete for a few seconds Press > Save – without pressing anything else.
   Upload and all should be good?
 *  [Bodhipaksa](https://wordpress.org/support/users/haecceity/)
 * (@haecceity)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381424)
 * > Upload and all should be good?
 * Unless he’s using a Mac, in which case he’s royally screwed himself, since the
   delete key works the same as backspace on a PC 🙂
 *  [ladydelaluna](https://wordpress.org/support/users/ladydelaluna/)
 * (@ladydelaluna)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381425)
 * umm… delete gets rid of everything past the cursor, without moving the cursor,
   but essentially “sucking up and destroying” everything beyond it. the backspace
   erases everything behind the cursor, while moving.
 * pods is correct… and no, the delete key and the backspace key do NOT do the same
   thing on a PC…
 *  [Bodhipaksa](https://wordpress.org/support/users/haecceity/)
 * (@haecceity)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381543)
 * What I meant was “the delete key [on a Mac] works the same as a backspace on 
   a PC”. I thought that was obvious that I was talking about the delete key on 
   a Mac when I wrote it, but I can see the ambiguity now.
 * I do know that the delete and backspace keys on a PC work in different direction.
 *  Thread Starter [freddymungo](https://wordpress.org/support/users/freddymungo/)
 * (@freddymungo)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381783)
 * Wow, Podz, thanks, that worked perfectly.
 * …
 * Why did that work?
 *  [Bodhipaksa](https://wordpress.org/support/users/haecceity/)
 * (@haecceity)
 * [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381795)
 * You had an extra line (or more) of whitespace below the last piece of code. What
   you were doing was deleting those extra lines.

Viewing 7 replies - 1 through 7 (of 7 total)

The topic ‘Errors whenever activating plugins’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 7 replies
 * 5 participants
 * Last reply from: [Bodhipaksa](https://wordpress.org/support/users/haecceity/)
 * Last activity: [19 years, 11 months ago](https://wordpress.org/support/topic/errors-whenever-activating-plugins/#post-381795)
 * Status: resolved

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