I believe you need to add the ability to connect to Google through an HTTP Proxy server. I would recommend the proxy settings to include a required Server IP/Name and port number and optionally a user name and password.
CalSync already works with an HTTP Proxy server. By default, it will detect the proxy settings in IE and use those. If nothing is found, or the connection is still not successful, CalSync should prompt you for a proxy server address, username, and password.
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CalSync already works with an HTTP Proxy server. By default, it will detect the proxy settings in IE and use those. If nothing is found, or the connection is still not successful, CalSync should prompt you for a proxy server address, username, and password.