Title: WordPress 3.0 Plugin Activation Error
Last modified: August 19, 2016

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# WordPress 3.0 Plugin Activation Error

 *  [iamkickstart](https://wordpress.org/support/users/iamkickstart/)
 * (@iamkickstart)
 * [15 years, 11 months ago](https://wordpress.org/support/topic/wordpress-30-plugin-activation-error/)
 * Hi,
 * I have problem with activating my own written plugin. My plugin have code like
   this:
 * plugins/Testing/test.php
    <?php /* Plugin Name: Testing Version: 0.1 Plugin URI:
   [http://www.testing.com](http://www.testing.com) Description: Testing Author:
   Testing Author URI: [http://www.testing.com](http://www.testing.com) */ ?> halo
 * When I try to activate this plugin, wordpress give this error:
 * “The plugin generated 4 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.”
 * When I try to logout from wordpress, it gives another long list of warning that
   prevent me from logging out.
 * Any idea how to fix this? Not sure is my settings problem or wordpress issue,
   so far it it working for wordpress 2.9.
 * Thanks

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

 *  [Mike Challis](https://wordpress.org/support/users/mikechallis/)
 * (@mikechallis)
 * [15 years, 11 months ago](https://wordpress.org/support/topic/wordpress-30-plugin-activation-error/#post-1544366)
 * Make sure there is no characters or whitespace before the `<?php` or after the`?
   >`
 *  [Robert Chapin](https://wordpress.org/support/users/miqrogroove/)
 * (@miqrogroove)
 * [15 years, 11 months ago](https://wordpress.org/support/topic/wordpress-30-plugin-activation-error/#post-1544562)
 * “halo” = 4 characters. WordPress considers this to be a corrupt plugin.
 *  [mpilon](https://wordpress.org/support/users/mpilon/)
 * (@mpilon)
 * [15 years, 10 months ago](https://wordpress.org/support/topic/wordpress-30-plugin-activation-error/#post-1544777)
 * Mike Challis-
 * Thanks for posting your comment. It saved me considerable time and trouble, as
   I definitely would not have come up with that on my own. Just one line of whitespace
   was destroying my efforts.
 * Thanks again,
 * matt pilon
 *  [deblopper.sumanta](https://wordpress.org/support/users/debloppersumanta/)
 * (@debloppersumanta)
 * [15 years, 3 months ago](https://wordpress.org/support/topic/wordpress-30-plugin-activation-error/#post-1544843)
 * User : Mike Challis
    User : miqrogroove You both gives exactly correct ans. Mike
   Challis’s ans helps me a lot. Thanks.

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

The topic ‘WordPress 3.0 Plugin Activation Error’ is closed to new replies.

## Tags

 * [wordpress 3.0](https://wordpress.org/support/topic-tag/wordpress-3-0/)

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 4 replies
 * 5 participants
 * Last reply from: [deblopper.sumanta](https://wordpress.org/support/users/debloppersumanta/)
 * Last activity: [15 years, 3 months ago](https://wordpress.org/support/topic/wordpress-30-plugin-activation-error/#post-1544843)
 * Status: not resolved

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