This thread is resolved. Here is a description of the problem and solution.
Problem:
How can I update WPML CMS Multilingual and String Translation
Solution:
If you're experiencing this issue, we recommend you try the following steps:
1. Navigate to Plugins → Add New and select the Commercial tab. Then, click 'Unregister WPML from this site'.
2. After the page loads, click on 'Register WPML'. You will see a prompt to enter the site key. Select 'Get a key for this site'.
3. In your WPML account, complete the site key wizard and set it to 'Production site'.
4. Copy your new key and paste it in the Commercial tab. Afterwards, you can delete your old site key in your WPML account.
5. Update your WPML plugins.
This solution might be irrelevant if it's outdated or not applicable to your case. We highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If the issue persists, please open a new support ticket at 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.