Title: [NSFW] Call to undefined function WP2FA\Authenticator\login_header() Last modified: September 19, 2022 --- # [NSFW] Call to undefined function WP2FA\Authenticator\login_header() * [Nayyer Abbas](https://wordpress.org/support/users/nayyer572/) * (@nayyer572) * [3 years, 8 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/) * Error Details ============= An error of type E_ERROR was caused in line 813 of the file /[…]/wp-content/plugins/wp-2fa/includes/classes/Authenticator/class- login.php. Error message: Uncaught Error: Call to undefined function WP2FA\Authenticator\ login_header() in /[…]/wp-content/plugins/wp-2fa/includes/classes/Authenticator/ class-login.php:813 Stack trace: #0 /[…]/wp/wp-includes/class-wp-hook.php(309): WP2FA\Authenticator\Login::login_form_validate_2fa(”) #1 /[…]/wp/wp-includes/ class-wp-hook.php(335): WP_Hook->apply_filters(NULL, Array) #2 /[…]/wp/wp-includes/ plugin.php(476): WP_Hook->do_action(Array) #3 /[…]/wp/wp-settings.php(620): do_action(‘ wp_loaded’) Viewing 4 replies - 1 through 4 (of 4 total) * Plugin Contributor [robertabela](https://wordpress.org/support/users/robert681/) * (@robert681) * [3 years, 8 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/#post-16033382) * Hello [@nayyer572](https://wordpress.org/support/users/nayyer572/) * Thank you for using our plugin and I am sorry to read that you are experiencing issues. * We’ll need more information from you to be able to understand the context of the issue. Can you please let us know: * 1) What version of WordPress, PHP and the plugin are you running? 2) When is this error happening? Is this happening when you activate the plugin, or when someone tries to log in? 3) Is this a new plugin install or is it an upgrade, and the previous version was working? * The more information you can share with us the better we can understand the issue. * Looking forward to hearing from you. * Plugin Contributor [robertabela](https://wordpress.org/support/users/robert681/) * (@robert681) * [3 years, 8 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/#post-16037132) * Hello [@nayyer572](https://wordpress.org/support/users/nayyer572/) * We’ve done some more troubleshooting it seems that a function that should be available during an interim login is not there. * The interim login is when you are already logged in to WordPress, your session expires and WordPress prompts you with a login prompt. * We are not sure what is causing this problem and if it is really happening only during the interim login, hence whey we are asking you for more information, to better understand the context of this issue. * Can you please confirm if this is actually happening when a user is already logged in and they are prompted with the interim login? Or does it happen in other scenarios? * Should you want to try it, we have prepared a patched version of the plugin that“ forces” the function to be there. [Click here to download](https://www.wpwhitesecurity.com/support/plugins-patches/) the _20220923 WP2FA v2.3.0 – undefined function_ patch. * Note that this is a blind fix and a workaround, not a solution. Even if it works, we would prefer to learn more about the problem and identify the cause rather than just working around it. If you’d like to help us, can you please send us the System Information file (from the “Help & Contact Us” section in he plugin) via email at [support@wpwhitesecurity.com](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/support@wpwhitesecurity.com?output_format=md)? * We’d like to see what other plugins you have installed on your website and other setup technical details. Please do not share the system information file on this forum since it contains technical details about your website’s setup. * Looking forward to hearing from you. * Thread Starter [Nayyer Abbas](https://wordpress.org/support/users/nayyer572/) * (@nayyer572) * [3 years, 8 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/#post-16042747) * Hi * Thanks for your response. * I am using 2FA plugin – 2.3.0 version, WordPress – 6.0.2 version, PHP – 7.4 version. * Yes you are right. The issue is When a user is already logged in to WordPress, user’s session expires and WordPress prompts you with a login prompt. After successful login. It shows critical error. * Regards, Nayyer - This reply was modified 3 years, 8 months ago by [Nayyer Abbas](https://wordpress.org/support/users/nayyer572/). * Plugin Contributor [robertabela](https://wordpress.org/support/users/robert681/) * (@robert681) * [3 years, 8 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/#post-16043464) * Hello [@nayyer572](https://wordpress.org/support/users/nayyer572/) * By any chance did you try to install the patch we’ve linked to in our last post? Viewing 4 replies - 1 through 4 (of 4 total) The topic ‘[NSFW] Call to undefined function WP2FA\Authenticator\login_header()’ is closed to new replies. * ![](https://ps.w.org/wp-2fa/assets/icon-256x256.png?rev=2961533) * [WP 2FA - Two-factor authentication for WordPress](https://wordpress.org/plugins/wp-2fa/) * [Frequently Asked Questions](https://wordpress.org/plugins/wp-2fa/#faq) * [Support Threads](https://wordpress.org/support/plugin/wp-2fa/) * [Active Topics](https://wordpress.org/support/plugin/wp-2fa/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/wp-2fa/unresolved/) * [Reviews](https://wordpress.org/support/plugin/wp-2fa/reviews/) * 8 replies * 2 participants * Last reply from: [robertabela](https://wordpress.org/support/users/robert681/) * Last activity: [3 years, 8 months ago](https://wordpress.org/support/topic/call-to-undefined-function-wp2faauthenticatorlogin_header-2/#post-16043464) * Status: not resolved