Title: PHP error
Last modified: February 4, 2020

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# PHP error

 *  Resolved [Sea Jay](https://wordpress.org/support/users/jcollier/)
 * (@jcollier)
 * [6 years, 3 months ago](https://wordpress.org/support/topic/php-error-363/)
 * Hi, John-
 * I deactivated Query Monitor during a debugging process and got the following 
   PHP error at the top of each webpage.
 * Notice: is_feed was called incorrectly. Conditional query tags do not work before
   the query is run. Before then, they always return false. Please see Debugging
   in WordPress for more information. (This message was added in version 3.1.0.)
   in /home/[snip]/wp-includes/functions.php on line 4986
 * Warning: Cannot modify header information – headers already sent by (output started
   at /home/[snip]/wp-includes/functions.php:4986) in /home/[snip]/wp-content/plugins/
   sg-cachepress/core/Supercacher/Supercacher_Helper.php on line 77
 * How would I figure out how to resolve this?
 * -Jay

Viewing 1 replies (of 1 total)

 *  Plugin Author [John Blackbourn](https://wordpress.org/support/users/johnbillion/)
 * (@johnbillion)
 * WordPress Core Developer
 * [6 years, 3 months ago](https://wordpress.org/support/topic/php-error-363/#post-12399358)
 * It looks from the error that the sg-cachepress plugin might be at fault. I would
   first make sure it’s up to date, and if that doesn’t fix the problem then get
   in touch with SiteGround.

Viewing 1 replies (of 1 total)

The topic ‘PHP error’ is closed to new replies.

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 * 1 reply
 * 2 participants
 * Last reply from: [John Blackbourn](https://wordpress.org/support/users/johnbillion/)
 * Last activity: [6 years, 3 months ago](https://wordpress.org/support/topic/php-error-363/#post-12399358)
 * Status: resolved