The error message “Updating failed. The response is not a valid JSON response” keep occurring whenever you performing the editing and saving the WordPress post.
Solution
There are multiple causes of resulting this error message, “Updating failed. The response is not a valid JSON response” and we manage to solve the issue with below workarounds. Our resolution might not be applicable to yours specifically but no harm trying it, correct? There are tons of blogs sharing about this issue and you might found another way of resolving the issue as well.
Before you proceed to the workarounds, please ensure below items are correctly maintain.
- The WordPress Address (URL) and Site Address (URL) area maintain with https.
- The htaccess file is exist and having the permissible to write.
Workaround 1
Reapply or re-save the permalinks settings. Do not change the permalink settings. Changing your permalinks settings can seriously impact your search engine visibility. It should almost never be done on a live website.
Workaround 2
This is applicable for those who has Really Simple SSL plugin installed. From the settings, enable the options for
- Mixed content fixes
- Use alternative method to fix mixed content.
Workaround 3
Use back the WordPress Classic Editor. You can download the plugin from here, https://wordpress.org/plugins/classic-editor/
