Title: Upgrade error invalid function Last modified: April 23, 2024 --- # Upgrade error invalid function * Resolved [SigalZ](https://wordpress.org/support/users/sigalz/) * (@sigalz) * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/) * Hello, * I am new to WordPress and I have a site with an old version (4.1.40) that I need to upgrade to version 6.5.2. After the upgrade I get this error:Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function “cptui_register_my_taxes_collection” not found or invalid function name in C:\wamp64\www\mysite.local\wp-includes\class-wp-hook.php on line 324This line is in file: wp-content\themes\HZ\functions.php.If I disable it, everything works fine.I would like to know if it is ok to disable it, I can’t find what is this code for.Is there a different function I should call instead? * Thank you Viewing 6 replies - 1 through 6 (of 6 total) * Plugin Contributor [Michael Beckwith](https://wordpress.org/support/users/tw2113/) * (@tw2113) * The BenchPresser * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707548) * Hi [@sigalz](https://wordpress.org/support/users/sigalz/) * To be certain, the site does have CPTUI installed and active correct? * That asked, we don’t specifically have a function named that, but the naming convention has me thinking you have/had a “collection” taxonomy that was originally created using CPTUI, and then code that would also register it got copy/pasted elsewhere. Probably the `HZ/functions.php` file. * However, based on that error, that function declaration got lost, or is maybe in a different file? * We make it easy for site owners to technically move away from using CPTUI directly, and still retain all of their established settings, or even treat it as a generator for content types. The biggest question here is going to be where the function went for you. * Thread Starter [SigalZ](https://wordpress.org/support/users/sigalz/) * (@sigalz) * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707674) * Hi [@tw2113](https://wordpress.org/support/users/tw2113/), * Thank you very much for answering me. * The site has CPTUI installed and active. * It is an old site that someone else developed. * I don’t understand your question ‘where the function went for you’? * What do you mean? * Plugin Contributor [Michael Beckwith](https://wordpress.org/support/users/tw2113/) * (@tw2113) * The BenchPresser * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707795) * Well, it’s not one we register or make use of for the core plugin. It’s one that we generate for registration export. * If you visit /wp-admin/admin.php?page=cptui_tools&action=get_code in your admin, you’ll see a bunch of textareas. One that outputs ALL the content types, and then more that export per content type. * For example, in one of my personal websites where I make use of CPTUI, I have this as one of the exportable items, for a taxonomy i named “book_status” * ```wp-block-code function cptui_register_my_taxes_book_status() { ... register_taxonomy( "book_status", [ "books" ], $args ); } add_action( 'init', 'cptui_register_my_taxes_book_status' ); ``` * Note the naming convention there, alongside your example from the original error:` cptui_register_my_taxes_collection`. * So, at some point, the site had a function named that, but it doesn’t any more. Something happened and its not being found, perhaps because it got removed from the functions.php file. * Hard for me to say from my spot here, as I don’t have access to the code in the install. * Thread Starter [SigalZ](https://wordpress.org/support/users/sigalz/) * (@sigalz) * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707831) * [@tw2113](https://wordpress.org/support/users/tw2113/) you are amazing! Thank you so much for the detailed answers. * From what you say, I will search for this function in all the files of the site before the upgrade, to see if it exists somewhere. The fact that everything works after upgrade if I disable it, makes me think it is probably a redundant code that is not actually used. * Plugin Contributor [Michael Beckwith](https://wordpress.org/support/users/tw2113/) * (@tw2113) * The BenchPresser * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707854) * We’re rooting for you. That said if you see “collections” listed when visiting say the “Registered Types and Taxes” menu item, it very much may be redundant at this time. * Thread Starter [SigalZ](https://wordpress.org/support/users/sigalz/) * (@sigalz) * [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707856) * Just a quick update, I went and checked the error file on the live site and this error is all this file has, so I guess with the upgrade, this error stops the site from running, when with the old site, it could still work with the error. Probably a php version.Again, thank you very much Viewing 6 replies - 1 through 6 (of 6 total) The topic ‘Upgrade error invalid function’ is closed to new replies. * ![](https://ps.w.org/custom-post-type-ui/assets/icon-256x256.png?rev=2744389) * [Custom Post Type UI](https://wordpress.org/plugins/custom-post-type-ui/) * [Frequently Asked Questions](https://wordpress.org/plugins/custom-post-type-ui/#faq) * [Support Threads](https://wordpress.org/support/plugin/custom-post-type-ui/) * [Active Topics](https://wordpress.org/support/plugin/custom-post-type-ui/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/custom-post-type-ui/unresolved/) * [Reviews](https://wordpress.org/support/plugin/custom-post-type-ui/reviews/) ## Tags * [upgrade-error](https://wordpress.org/support/topic-tag/upgrade-error/) * 6 replies * 2 participants * Last reply from: [SigalZ](https://wordpress.org/support/users/sigalz/) * Last activity: [2 years, 1 month ago](https://wordpress.org/support/topic/upgrade-error-invalid-function/#post-17707856) * Status: resolved