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This topic contains 3 replies, has 2 voices.

Last updated by Geert C. 5 months, 2 weeks ago.

Assigned support staff: Mihai Apetrei.

Author Posts
May 7, 2019 at 3:39 pm #3759839

Geert C.

Tell us what you are trying to do?

Is there any documentation that you are following?

Is there a similar example that we can see?

What is the link to your site? outdoorsweden.com

May 7, 2019 at 3:40 pm #3759841

Geert C.

Fatal error: Uncaught Error: Undefined class constant 'PAGE_SLUG_SETTINGS' in D:\appdata\IIS\vhosts\outdoorsweden.com\httpdocs\wp-content\plugins\sitepress-multilingual-cms\classes\utilities\admin\class-wpml-admin-url.php:7 Stack trace: #0 D:\appdata\IIS\vhosts\outdoorsweden.com\httpdocs\wp-content\plugins\sitepress-multilingual-cms\classes\upgrade\commands\class-wpml-upgrade-display-mode-for-posts.php(83): WPML_Admin_URL::multilingual_setup(7) #1 D:\appdata\IIS\vhosts\outdoorsweden.com\httpdocs\wp-content\plugins\sitepress-multilingual-cms\classes\upgrade\commands\class-wpml-upgrade-display-mode-for-posts.php(29): WPML_Upgrade_Display_Mode_For_Posts->get_notice_content() #2 D:\appdata\IIS\vhosts\outdoorsweden.com\httpdocs\wp-content\plugins\sitepress-multilingual-cms\classes\upgrade\class-wpml-upgrade.php(146): WPML_Upgrade_Display_Mode_For_Posts->run_admin() #3 D:\appdata\IIS\vhosts\outdoorsweden.com\httpdocs\wp-content\plugins\sitepress-multilingual-cms\classes\upgrade\class-wpml-upgrade.php(134): WPML_Upgrade->maybe_r in D:\appdata\IIS\vhosts\outdoorsweden.com\httpdocs\wp-content\plugins\sitepress-multilingual-cms\classes\utilities\admin\class-wpml-admin-url.php on line 7

May 7, 2019 at 5:04 pm #3760871

Mihai Apetrei
Supporter

Languages: English (English )

Timezone: Europe/Bucharest (GMT+03:00)

Hi and thank you for contacting WPML Support!

I will be happy to help you with this.

From what I can see in older tickets, there might be updates missing from other WPML plugins and that is the reason that you might see that error.

Here are a few similar tickets I have found:
- https://wpml.org/forums/topic/fatal-error-uncaught-error-undefined-class-constant-page_slug_settings/
- https://wpml.org/forums/topic/error-when-trying-to-update-plugin/
- https://wpml.org/forums/topic/fatal-error-123/

Please create a full website backup, and after that disable and uninstall/delete the WPML plugins and try to install them manually following the procedure found here:
https://wpml.org/faq/install-wpml/#updating-manually

Please let me know if this solved your issue or if you still need help.

I will be waiting for your response.

Just a note that I am at the end of my shift at the moment and I will be able to answer you tomorrow if you reply tonight.

Kind regards,
Mihai Apetrei

May 10, 2019 at 4:48 am #3781361

Geert C.

My issue is resolved now. Thank you!