Title: Undefined/cannot modify header
Last modified: January 31, 2023

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# Undefined/cannot modify header

 *  Resolved [cshinkin](https://wordpress.org/support/users/cshinkin/)
 * (@cshinkin)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/)
 * Hi I recently added your very good plugin for a future product but I am seeing
   an error when logging in as a customer.
 * Warning: Undefined array key “uwa-new-redirect” in /homepages/3… …/plugins/ultimate-
   woocommerce-auction/includes/class-uwa-front.php on line 1133
 * Warning: Cannot modify header information – headers already sent by (output started
   at /homepages/3… …SSArt/wp-includes/pluggable.php on line 1416
 * Warning: Cannot modify header information – headers already sent by (output started
   at /homepages/3… …SSArt/wp-includes/pluggable.php on line 1419
 * For now I have deactivated.
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fundefined-cannot-modify-header%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 6 replies - 1 through 6 (of 6 total)

 *  Plugin Author [Nitesh](https://wordpress.org/support/users/nitesh_singh/)
 * (@nitesh_singh)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16426162)
 * Hi [@cshinkin](https://wordpress.org/support/users/cshinkin/) ,
 * Apologies for an inconvenience.
 * The first thing that I wanted to point to you is that since you are using our
   free plugin and want to display “Future Auction Products” then there isn’t a 
   separate shortcode in free plugin to do it. Our “Pro Plugin” has separate shortcodes
   for future, live and past auction products.
 * With regards to the error, we would like more information to reproduce it:
    1. Could you please share WooCommerce System Report? It can be found – WP Admin
       > WooCommerce > Status > Get System Report.
       This will help us analyze the WordPress
       setup that you are running and will give us an idea if WP and related softwares
       used are using the latest version or not.
    2. Are you using a paid theme? If that is so, sometimes there are certain javascript
       or css conflicts due to which such errors come. Please send us the theme zip
       so that we can check it in our local test setup.
    3. The scenario that we have understood is the following:
    4.  - Install our free plugin
        - Add an auction product
        - Register a new user
        - Login with new user and you see the above error
 * Is the above test steps correct? If not, please mention it.
 * Regards,
 * Nitesh
 *  Thread Starter [cshinkin](https://wordpress.org/support/users/cshinkin/)
 * (@cshinkin)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16426858)
 * System Report attached. Yes the product auction is set as live but not yet Published
   so as to troubleshoot. Woo customers can make accounts and while this was a ‘
   live’ auction I decided to log in with my existing account as if I was a customer.
 * The theme is Storefront so not paid.
 * [https://drive.google.com/file/d/1h9QQFpChv-dFWixImdEqOPq732ER89cH/view?usp=sharing](https://drive.google.com/file/d/1h9QQFpChv-dFWixImdEqOPq732ER89cH/view?usp=sharing)
 *  [payalrajyaguru](https://wordpress.org/support/users/payalrajyaguru/)
 * (@payalrajyaguru)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16432017)
 * Hi [@cshinkin](https://wordpress.org/support/users/cshinkin/),
   1) We have checked
   this query on our server. But we did not find any issue. Please review the attached
   video. [https://we.tl/t-stPvADduEO](https://we.tl/t-stPvADduEO)
 * 2) It looks like the Ultimate Auction for WooCommerce plugin is deactivated on
   your site. We need to check this query on your site. If it is possible for you
   to share the details below, it would be really helpful to solve your problem.
   -
   > Create a live auction product on your site and share its URL. -> Also share
   the credential for an existing customer of your site.3) Also, it might be the
   case where this issue might be occurring due to JavaScript code conflict with
   some other plugin. Could you please do the following and let us know its result:
 * Activate auction plugin. Then one by one, please deactivate other plugins installed
   on your website and see if this error goes away. When you find the plugin on 
   whose deactivation, this error goes away, then please share with us the plugin
   name so that we can test ourselves and check the issue.
   4) Please record a video
   for this issue and share it with us. So, we will get a clear idea about it. 
 * Please use [this contact form](https://auctionplugin.net/contact-us/) for answering
   the above query. We will check it and let you know.
   Thank You
 *  Thread Starter [cshinkin](https://wordpress.org/support/users/cshinkin/)
 * (@cshinkin)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16432738)
 * Login and a test product link sent to your linked form under the presales tab.
 * – Colin
 *  Thread Starter [cshinkin](https://wordpress.org/support/users/cshinkin/)
 * (@cshinkin)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16433138)
 * Oops sincerest apologies plugin activated.
 *  Plugin Author [Nitesh](https://wordpress.org/support/users/nitesh_singh/)
 * (@nitesh_singh)
 * [3 years, 3 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16459566)
 * This issue has been resolved.

Viewing 6 replies - 1 through 6 (of 6 total)

The topic ‘Undefined/cannot modify header’ is closed to new replies.

 * ![](https://ps.w.org/ultimate-woocommerce-auction/assets/icon-256x256.gif?rev
   =2682280)
 * [Ultimate Auction for WooCommerce - Excellent WP Auction Plugin](https://wordpress.org/plugins/ultimate-woocommerce-auction/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/ultimate-woocommerce-auction/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/ultimate-woocommerce-auction/)
 * [Active Topics](https://wordpress.org/support/plugin/ultimate-woocommerce-auction/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/ultimate-woocommerce-auction/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/ultimate-woocommerce-auction/reviews/)

 * 8 replies
 * 3 participants
 * Last reply from: [Nitesh](https://wordpress.org/support/users/nitesh_singh/)
 * Last activity: [3 years, 3 months ago](https://wordpress.org/support/topic/undefined-cannot-modify-header/#post-16459566)
 * Status: resolved