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1) Configuration settings seem correct but I see this error message when accessing to pages related to "Lists configuration" and "Users import" (see picture below):
Please ensure that in "Settings > Account settings > Developer's corner > Web services" you have added the IP of your server on which Drupal is running (you can add more than one address). If you are unable to identify the IP address you can disable IP validation.
2) I have updated Drupal module and the following error is returned:
Please execute command "Flush all caches"