Title: Showing error in debug mode
Last modified: August 21, 2016

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# Showing error in debug mode

 *  [Mayeenul Islam](https://wordpress.org/support/users/wzislam/)
 * (@wzislam)
 * [12 years, 4 months ago](https://wordpress.org/support/topic/showing-error-in-debug-mode/)
 * With WP_DEBUG true, the following errors are showing by WP Minfy in my installation:
 * This error is showing on every page in front-end only:
 * > 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.) in /home/…/public_html/wp-includes/functions.php on line 3049
 * And specifically in `/wp-login.php`, with the is_feed error two other errors 
   are showing:
 * > Warning: Cannot modify header information – headers already sent by (output
   > started at /home/…/public_html/wp-includes/functions.php:3049) in /home/…/public_html/
   > wp-login.php on line 415
 * > Warning: Cannot modify header information – headers already sent by (output
   > started at /home/…/public_html/wp-includes/functions.php:3049) in /home/…/public_html/
   > wp-login.php on line 427
 * Thank you.
 * [http://wordpress.org/plugins/wp-minify/](http://wordpress.org/plugins/wp-minify/)

Viewing 1 replies (of 1 total)

 *  [Kimberly](https://wordpress.org/support/users/kellogg9/)
 * (@kellogg9)
 * [12 years, 3 months ago](https://wordpress.org/support/topic/showing-error-in-debug-mode/#post-4477810)
 * You should prolly disable wp minify when it deals with Admin (e.g. u logging 
   in). i most certainly dont have wp-minify applying any of its tricks when i attempt
   to login…seems like a waste (only useful for visitors of a site not me managing
   the website).

Viewing 1 replies (of 1 total)

The topic ‘Showing error in debug mode’ is closed to new replies.

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## Tags

 * [Cannot modify header information](https://wordpress.org/support/topic-tag/cannot-modify-header-information/)
 * [errors](https://wordpress.org/support/topic-tag/errors/)
 * [is_feed](https://wordpress.org/support/topic-tag/is_feed/)

 * 1 reply
 * 2 participants
 * Last reply from: [Kimberly](https://wordpress.org/support/users/kellogg9/)
 * Last activity: [12 years, 3 months ago](https://wordpress.org/support/topic/showing-error-in-debug-mode/#post-4477810)
 * Status: not resolved