Critical Error from WordPress Update

What is the PHP version you are using for this website? If possible, try to change your PHP version (the current recommended version is PHP 7.4)

You will need to do some troubleshooting to rule out the conflict of a plugin or theme with your current version of WordPress or PHP. For this you will need to access your site files either through an FTP client such as Filezilla, or through the File Manager in the control panel provided by your host (e.g. cPanel).

If you can access your site files through either of these routes, then you would need to navigate to /wp-content/plugins/ and rename this directory to /wp-content/plugins.hold (this will deactivate all your plugins). If this does not allow you normal access, then also switch to the default WordPress theme by changing /wp-content/themes/{your theme} to /wp-content/themes/{your theme}.hold. This should force the default WordPress theme (e.g. Twenty-Twenty) to be activated, providing you have one in your themes directory. Then try and access. If either/both of these methods resolves the issue then a) rename the directories back to /wp-content/plugins/ and /wp-content/themes/, log into the WordPress dashboard and reactivate the plugins/theme one by one until you find the conflicting one.

• This reply was modified 5 years, 9 months ago by barnez. Reason: Fix typo

It’s possible that the update failed to complete. I would download a fresh version of 5.5 from here. Then, delete and replace all the WordPress files and directories *except* the wp-config.php file and the /wp-content/ directory. Note that delete and replace rather than overwrite is important.

Also note that enabling debug to true in wp-config.php is not intended to fix the problem. Once debugging is enabled you should see some error code(s) when you try and visit the site, which will point towards the problem.

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