Title: undefined function trailingslashit Last modified: December 3, 2022 --- # undefined function trailingslashit * Resolved [ukracer](https://wordpress.org/support/users/ukracer/) * (@ukracer) * [3 years, 6 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/) * [03-Dec-2022 18:38:14 Europe/London] PHP Fatal error: Uncaught Error: Call to undefined function trailingslashit() in /home/westmidl/public_html/wp/wp-includes/ class-wp-textdomain-registry.php:103 * I have been trying to update the php version to 7.4 but it just gives a white screen. Having been through a lot of suggestions, I just can’t find the answer to my problem. Most likely, as I don’t know what to search for. * When I search for any terms in the error log it seems to all relate to a plugin. But mine does not as far as I can tell… * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Fundefined-function-trailingslashit%2F%3Foutput_format%3Dmd&locale=en_US) to see the link]_ Viewing 6 replies - 1 through 6 (of 6 total) * Thread Starter [ukracer](https://wordpress.org/support/users/ukracer/) * (@ukracer) * [3 years, 6 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16257862) * I think I might have found the solution in another thread. sadly I cant upload the wp-includes using the file manager in CPanel.. * Thread Starter [ukracer](https://wordpress.org/support/users/ukracer/) * (@ukracer) * [3 years, 6 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16258099) * well just to update things I have now managed to upload the complete folder wp- includes but it now comes up with Your PHP installation appears to be missing the MySQL extension which is required by WordPress. * so I am stuck even more now. 🙁 * [George Appiah](https://wordpress.org/support/users/gappiah/) * (@gappiah) * [3 years, 6 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16258331) * Seems you’ve resolve your issue now, as your site works perfectly from my side of the pond 😀 * Thread Starter [ukracer](https://wordpress.org/support/users/ukracer/) * (@ukracer) * [3 years, 6 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16258481) * Well yes it’s working so thanks for looking at thread. I was having terrible problems connecting via FTP to replace the wp-includes folder. * So I asked my hosts what was wrong. I finally managed to get 1 of the 3 ftp programs to connect. * While that was happening I uploaded the folder but now I got a different error.( About sql missing) I found reference to that error but what I did looked like it had not solved it. * While I was doing this my hosts had noticed something wrong with php files and restored them. Now it worked OK. But not sure what fixed it…..although I suspect it was what tech support actually did that solved it. * Thread Starter [ukracer](https://wordpress.org/support/users/ukracer/) * (@ukracer) * [3 years, 6 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16258720) * This was the support reply/.. in case anyone has a similar issue. * “In relation to the PHP issues with MySQL I have re-set the ‘westmidl’ to the default PHP modules for the selected PHP v7.4 since I noticed it had quite a few modules missing.” * [jazzyjeff1](https://wordpress.org/support/users/jazzyjeff1/) * (@jazzyjeff1) * [3 years, 5 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16316145) * Whenever I try to update a plugin I do have the same error : * `atal error: Uncaught Error: Call to undefined function trailingslashit() in / home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/web/wp-includes/class-wp-textdomain- registry.php:103 Stack trace: #0 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/ web/wp-includes/l10n.php(784): WP_Textdomain_Registry->set('default', 'fr_FR','/ home/clients/7...') #1 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/web/wp- includes/load.php(1401): load_textdomain('default', '/home/clients/7...', 'fr_FR')# 2 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/web/wp-includes/load.php(278): wp_load_translations_early() #3 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/ web/wp-settings.php(74): wp_maintenance() #4 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/ web/wp-config.php(99): require_once('/home/clients/7...') #5 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/ web/wp-load.php(50): require_once('/home/clients/7...') #6 /home/clients/7c35a8964cfc8a2ffa4301e404f5f71d/ web/wp-blog-header.php(13): require_once('/home/clients/7...') #7 /home/clients/ 7c35a8964cfc8a2ffa4301e404f5f71d/web/index.php(17): require('/home/clients/7...')# 8 {main} thrown in /home/clients/` * Any idea to solve this ? I can repair the website by restoring a previous saved version or uploading the “wp-includes” directory Viewing 6 replies - 1 through 6 (of 6 total) The topic ‘undefined function trailingslashit’ is closed to new replies. * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/) * 6 replies * 3 participants * Last reply from: [jazzyjeff1](https://wordpress.org/support/users/jazzyjeff1/) * Last activity: [3 years, 5 months ago](https://wordpress.org/support/topic/undefined-function-trailingslashit/#post-16316145) * Status: resolved ## Topics ### Topics with no replies ### Non-support topics ### Resolved topics ### Unresolved topics ### All topics