Title: Error in DEBUG
Last modified: March 23, 2023

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# Error in DEBUG

 *  Resolved [NunyaBiznus](https://wordpress.org/support/users/candycrusher/)
 * (@candycrusher)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/error-in-debug-2/)
 * I ran the debug on my test site and this is what the errors came out.
 * **Notice**: Function is_singular 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](https://wordpress.org/support/article/debugging-in-wordpress/)
   for more information. (This message was added in version 3.1.0.) in **/test/wp-
   includes/functions.php** on line **5835**
 * **Notice**: woocommerce_recently_viewed cookie cannot be set – headers already
   sent by /test/wp-includes/functions.php on line 5835 in **/test/wp-content/plugins/
   woocommerce/includes/wc-core-functions.php** on line **1101**
 * Thanks.

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

 *  [xue28 (woo-hc)](https://wordpress.org/support/users/xue28/)
 * (@xue28)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/error-in-debug-2/#post-16590574)
 * Hi [@candycrusher](https://wordpress.org/support/users/candycrusher/)
 * Thanks for reaching out!
 * I understand that you receive the error messages above after running the debug
   test on your site.
 * Can you please share if there are any custom codes on your site’s `functions.
   php` that produce this error?
 * Another way to find out is by running a [full conflict test](https://woocommerce.com/document/how-to-test-for-conflicts/)
   to verify the root cause of this issue.
 * Let us know how it goes!
 *  Thread Starter [NunyaBiznus](https://wordpress.org/support/users/candycrusher/)
 * (@candycrusher)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/error-in-debug-2/#post-16592223)
 * Hi,
 * Yes I found when I activated the plugin YITH WooCommerce Order & Shipment Tracking
   that the error came out. Updated plugin error is gone.
 * You can delete this thread.
 * Thanks.
 *  [Saif](https://wordpress.org/support/users/babylon1999/)
 * (@babylon1999)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/error-in-debug-2/#post-16594525)
 * You’re very welcome, [@candycrusher](https://wordpress.org/support/users/candycrusher/)!
   😃
 * I will mark the thread as solved. If you have a few minutes, we’d love it if 
   you could leave us a review: [https://wordpress.org/support/plugin/woocommerce/reviews/](https://wordpress.org/support/plugin/woocommerce/reviews/)
 * Cheers!

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

The topic ‘Error in DEBUG’ is closed to new replies.

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 * 3 replies
 * 3 participants
 * Last reply from: [Saif](https://wordpress.org/support/users/babylon1999/)
 * Last activity: [3 years, 2 months ago](https://wordpress.org/support/topic/error-in-debug-2/#post-16594525)
 * Status: resolved