Fatal error: Uncaught Error: Class 'WPML\FP\Relation' not found

This thread is resolved. Here is a description of the problem and solution.

Problem:
The client is experiencing a fatal error after installing a new version of WPML on top of an old version without updating it. The error message indicates that the class 'WPML\FP\Relation' is not found.
Solution:
We recommend installing WPML plugins using the OTGS Installer to ensure all necessary files are present. For detailed instructions, please follow our documentation: https://wpml.org/faq/install-wpml/

If this solution does not resolve the issue, please do not hesitate to open a new support ticket with us: WPML Support Forum

This is the technical support forum for WPML - the multilingual WordPress plugin.

Everyone can read, but only WPML clients can post here. WPML team is replying on the forum 6 days per week, 22 hours per day.

Tagged: Exception

This topic contains 1 reply, has 2 voices.

Last updated by Long Nguyen 1 year, 3 months ago.

Assisted by: Long Nguyen.

Author	Posts
February 1, 2024 at 1:08 pm #15255054
ryoY-2	Tell us what you are trying to do? A few years ago, I was using WPML. The site had version 4.2.7.1 installed. Today, I made a new payment and installed version 4.6.9, while the old version remained. (I did a fresh installation, not an update.) During that time, an error like this was displayed. What should I do? ----- Fatal error: Uncaught Error: Class 'WPML\FP\Relation' not found in /home/path3/iricosky.com/public_html/wp/wp-content/plugins/sitepress-multilingual-cms/classes/query-filtering/class-wpml-term-query-filter.php:82 Stack trace: #0 /home/path3/iricosky.com/public_html/wp/wp-content/plugins/sitepress-multilingual-cms/sitepress.class.php(2518): WPML_Term_Query_Filter->get_terms_args_filter(Array, Array) #1 /home/path3/iricosky.com/public_html/wp/wp-includes/class-wp-hook.php(310): SitePress->get_terms_args_filter(Array, Array) #2 /home/path3/iricosky.com/public_html/wp/wp-includes/plugin.php(205): WP_Hook->apply_filters(Array, Array) #3 /home/path3/iricosky.com/public_html/wp/wp-includes/class-wp-term-query.php(408): apply_filters('get_terms_args', Array, Array) #4 /home/path3/iricosky.com/public_html/wp/wp-includes/class-wp-term-query.php(308): WP_Term_Query->get_terms() #5 /home/path3/iricosky.com/public_html/wp/wp-includes/taxonomy.php(1308): WP_Term_Query->query(Array) #6 /home/path3/iricosky.com/public_html/wp/wp-includes in /home/path3/iricosky.com/public_html/wp/wp-content/plugins/sitepress-multilingual-cms/classes/query-filtering/class-wpml-term-query-filter.php on line 82 ----- Furthermore, no specific errors have occurred since then.
February 2, 2024 at 2:35 am #15257342
Long Nguyen WPML Supporter since 02/2022 Languages: English (English ) Timezone: Asia/Ho_Chi_Minh (GMT+07:00)	Hi Ryo, Thank you for contacting WPML support, I'd be happy to help you with this issue. The issue is mostly related to the file missing when installing the plugin WPML. I suggest you install WPML plugins through the plugin OTGS installer and recheck this issue. Please follow the documentation https://wpml.org/faq/install-wpml/ While checking the debug info, I see that the WordPress Memory Limit is below the requirements. The minimum requirements are 128M, but we do recommend 256M and the debug information of your site shows it set to 40M. Please check this link for more details https://wpml.org/home/minimum-requirements/. You can increase it by adding the following code in your wp-config.php file, right before the /* That’s all, stop editing! Happy publishing. */ line: define( 'WP_MAX_MEMORY_LIMIT', '256M' ); define( 'WP_MEMORY_LIMIT', '128M' ); After adding the code you can confirm that the memory was changed correctly from WPML > Support > WordPress > Memory limit. Look forward to your reply. Thanks
February 2, 2024 at 4:03 am #15257451
ryoY-2	Hi long, Hello. Thank you for the accurate support. After increasing the memory limit and installing from the OTGS installer, the issue did not occur. Thank you very much.