Title: [Plugin: WP Super Cache] Cannot modify header information – headers already sent by
Last modified: August 19, 2016

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# [Plugin: WP Super Cache] Cannot modify header information – headers already sent by

 *  [podictionary](https://wordpress.org/support/users/podictionary/)
 * (@podictionary)
 * [17 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-cannot-modify-header-information-headers-already-sent-by/)
 * running WordPress 2.6.3 with WP Super Cache 0.8.4 “half on” mode
 * when first appearing pages on the blog show warning message (below), refresh 
   and the warning goes away, Super Cache off, goes away too.
 * Warning: preg_match() [function.preg-match]: Compilation failed: nothing to repeat
   at offset 0 in [my-webhost-directory]/wp-content/plugins/wp-super-cache/wp-cache-
   phase2.php on line 87
 * Warning: Cannot modify header information – headers already sent by (output started
   at [my-webhost-directory]/wp-content/plugins/wp-super-cache/wp-cache-phase2.php:
   87) in [my-webhost-directory]/wp-content/plugins/wp-super-cache/wp-cache-phase2.
   php on line 38 [followed by two appearances of ShareThis followed by the web 
   page as it should look]

Viewing 3 replies - 1 through 3 (of 3 total)

 *  [Donncha O Caoimh (a11n)](https://wordpress.org/support/users/donncha/)
 * (@donncha)
 * [17 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-cannot-modify-header-information-headers-already-sent-by/#post-887818)
 * That’s the reject uri check. Do you have anything in that textarea in the admin
   page? Are you using some PHP accelerator?
 * Don’t show php warnings/errors and you won’t see the error which is a temporary
   fix.
 *  [iridiax](https://wordpress.org/support/users/iridiax/)
 * (@iridiax)
 * [17 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-cannot-modify-header-information-headers-already-sent-by/#post-887830)
 * See: [Headers already sent](http://codex.wordpress.org/Answers-Troubleshooting#Headers_already_sent)
 *  Thread Starter [podictionary](https://wordpress.org/support/users/podictionary/)
 * (@podictionary)
 * [17 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-cannot-modify-header-information-headers-already-sent-by/#post-887873)
 * Thanks donncha
    The URI check seemed to come with the following already there
   wp-.*.php index.php
 * I added also
    ?s=
 * IF I’m using a PHP accelerator I don’t know about it.
 * Sorry, I also don’t know how not to show warnings (though I’d rather get the 
   fix)

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘[Plugin: WP Super Cache] Cannot modify header information – headers already
sent by’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 3 replies
 * 3 participants
 * Last reply from: [podictionary](https://wordpress.org/support/users/podictionary/)
 * Last activity: [17 years, 7 months ago](https://wordpress.org/support/topic/plugin-wp-super-cache-cannot-modify-header-information-headers-already-sent-by/#post-887873)
 * Status: not resolved

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