I'm working with a fresh Drupal 8 site installed on Acquia Dev Desktop.
I'm working to install the Address (https://www.drupal.org/project/address) module. This module requires the Composer Manager (https://www.drupal.org/project/composer_manager) module as well as some external PHP libraries managed by composer.
As part of the process of installing the Address module, I need to run "composer update" on the root of the Drupal 8 site. When I attempt to do this from within the Acquia Dev Desktop Drush Console window, I consistently get OpenSSL errors.
I had a colleague try the exact same thing with the exact same result.
When I run composer update from outside of the Acquia Dev Desktop Drush Console window, I do not get this error.