Fatal error: Uncaught Error: Class "WP_Upgrader_Skin" not found

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Tagged: Exception

This topic contains 21 replies, has 2 voices.

Last updated by lukasB-4 1 year, 10 months ago.

Assisted by: Bruno Kos.

Author	Posts
May 24, 2023 at 1:54 pm #13708191
lukasB-4	I am trying to: install WPML bug getting this error Link to a page where the issue can be seen: (admin only) hidden link Fatal error: Uncaught Error: Class "WP_Upgrader_Skin" not found in /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-content/plugins/sitepress-multilingual-cms/vendor/otgs/installer/includes/class-installer-upgrader-skins.php:3 Stack trace: #0 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-content/plugins/sitepress-multilingual-cms/vendor/otgs/installer/includes/class-otgs-installer-autoloader.php(18): include() #1 [internal function]: OTGS_Installer_Autoloader->autoload() #2 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-includes/functions.php(649): unserialize() #3 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-includes/option.php(253): maybe_unserialize() #4 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-includes/cron.php(1181): get_option() #5 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-includes/cron.php(763): _get_cron_array() #6 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-includes/cron.php(815): wp_get_scheduled_event() #7 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-admin/includes/class-wp-site-health.php(3003): wp_next_scheduled() #8 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-admin/includes/class-wp-site-health.php(38): WP_Site_Health->maybe_create_scheduled_event() #9 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-admin/includes/class-wp-site-health.php(81): WP_Site_Health->__construct() #10 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-settings.php(607): WP_Site_Health::get_instance() #11 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-config.php(98): require_once('/home/985131.cl...') #12 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-load.php(50): require_once('/home/985131.cl...') #13 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-admin/admin.php(34): require_once('/home/985131.cl...') #14 /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-admin/index.php(10): require_once('/home/985131.cl...') #15 {main} thrown in /home/985131.cloudwaysapps.com/vepackkcdn/public_html/wp-content/plugins/sitepress-multilingual-cms/vendor/otgs/installer/includes/class-installer-upgrader-skins.php on line 3
May 24, 2023 at 3:30 pm #13709457
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, Thank you for contacting WPML support! Can you download WPML from here and remove the version you have? https://wpml.org/download/wpml-multilingual-cms/?section=changelog Download Version 4.6.3. The error message you have typically indicate missing files that may happen due to failed upgrades or unzipping or other unforeseen reasons. Regards, Bruno Kos
May 25, 2023 at 10:27 am #13715205
lukasB-4	Downloaded + uploaded manually, but still the same error. Any other idea?
May 25, 2023 at 12:10 pm #13716023
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, Would you be willing to provide me with WordPress credentials so I could investigate the issue directly? Also can you install https://wordpress.org/plugins/wp-file-manager/? So this happens if you try activating WPML? Where does the issue occur, upon activating? https://wpml.org/purchase/support-policy/privacy-and-security-when-providing-debug-information-for-support/ I marked your next reply as private so that you can safely add credentials. Regards, Bruno Kos
May 29, 2023 at 5:47 am #13728861
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, I am unable to go through server protection - I entered credentials multiple times but it doesn't work. Regards, Bruno Kos
May 31, 2023 at 9:42 am #13745057
lukasB-4	Can you try it now with the previous details? If it will not work, I can change them and send in new private message.
May 31, 2023 at 10:15 am #13745593
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, These don't work even after multiple attempts to login. Regards, Bruno Kos
June 1, 2023 at 6:09 am #13750809
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, I am referring to this, I can't pass through it. I tried several times but it doesn't allow me to enter. Regards, Bruno Kos
June 1, 2023 at 7:38 am #13751379
lukasB-4	OK, I don't know why it is not working for you. Tested on several devices. I have disabled htpasswd for you, so you should be able to access the site now. Can you confirm?
June 1, 2023 at 10:42 am #13753091
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, It asks me for server credentials even in incognito mode. Regards, Bruno Kos
June 1, 2023 at 3:49 pm #13756235
lukasB-4	What is your URL? hidden link
June 2, 2023 at 6:04 am #13758405
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, That's the one. Regards, Bruno Kos
June 2, 2023 at 6:36 am #13758469
lukasB-4	Hi Bruno, can you try now?
June 2, 2023 at 10:09 am #13760539
Bruno Kos WPML Supporter since 12/2018 Languages: English (English ) German (Deutsch ) French (Français ) Timezone: Europe/Zagreb (GMT+02:00)	Hi, I was able to get in - I reinstalled plugins through file manager and I can see that it works now: hidden link Regards, Bruno Kos
June 3, 2023 at 7:52 am #13764041
lukasB-4	I have tried to finish the WPML configuration (in WPML settings) and we have the same error again. Can you check?

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