Instructions for allowing Google Drive to be accessed via a Smoothwall web filter.
Google Drive doesn't connect through an authenticated proxy.
Google Drive does work with a proxy server, however it does not support authentication for those connections. For this to work seamlessly for your users, you can set up Google Drive as an authentication bypass.
Note: Setting up Google Drive as an authentication exception prevents easy user tracking of those domain hits. This is because the domains in question are very broad and other Google applications may use the same addresses.