We only support proxies that use basic authentication, we do not support NTLM (Windows Integrated Authentication). Proxy auto-config (PAC) file configurations are not currently supported.
To enter a Network Proxy configuration, open the Desktop Sync settings page (http://127.0.0.1:8806/do_sync_preferences) and you will find the Network Proxy settings.
Let's take the example below:
Proxy Server Name: myproxyserver1
Proxy Port: 8080
If your network proxy requires a username and password, check the Proxy server requires username and password box.