Configuration Management Import page "The directory ../config/default is not writable." error

Issue

I have configured my Acquia site configuration directory according to Importing a configuration directory but I see the following error at admin/config/development/configuration/full/import :

The directory ../config/default is not writable.

Cause

Because the Acquia platform sets the code base for your site to read-only this message appears for Drupal Configuration Management. By default, Drupal expects a writeable directory for proposed import/export configuration files to be managed. Configuration Management files can still be placed in the directory via code deployments and imports will be successful. With the configuration directory pointing at config/default directory, this message will remain but configuration management imports can still take place.

Resolution

Configuration files that you wish to be imported onto the Acquia platform need to be added to your codebase through your standard version control systems. Deploy that code to the Acquia platform. Once the code containing the updated configuration is uploaded, files can be imported via the Synchonize tab or drush commands.

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