DavidD Hello, I'm a rookie with OpenVPN. I setup an openVPN as server at home on my lab environnement on 2K8R2 SP1 (listening on TCP/443) I installed open VPN on a Windows XP client. I'm well connecting on tcp/443 port without HTTP proxy. At office, we use a TMG HTTP proxy. So I added the line "http-proxy IPAddressOfMyProxy 80 ..\\config\\auth.txt ntlm" in my client configuration file. Auth.txt contains 2 lines : Line 1 : "CorpDomain\UserDomain" Line 2 : "password" No carriage return on line 3 (No line 3) I'm not connecting with HTTP proxy and NTLM (This TMG proxy does not provide Basic Auth, I can only use NTLM). WireShark said that openvpn Send 'Malformed Packet' in NTLM Auth (Why ?) The Open VPN log on client said : Thu Aug 23 14:58:43 2012 us=31000 Attempting NTLM Proxy-Authorization phase 3 Thu Aug 23 14:58:43 2012 us=31000 NTLM Proxy-Authorization phase 3 failed: received corrupted data from proxy server Thu Aug 23 14:58:43 2012 us=31000 TCP/UDP: Closing socket I uses OpenVPN 2.2.2 as client (downloaded today). Any help will be apreciated. Thank you.