Unless other changes have been made to the windows service, I'd recommend not using it at all. There are error conditions under which it just hangs and blocks openvpn.exe from working
We moved to using nssm - we set it to auto-restart on error and now openvpn as a Windows service is as reliable as openvpn as a Unix service Jason -- Cheers Jason Haar Corporate Information Security Manager, Trimble Navigation Ltd. Phone: +1 408 481 8171 PGP Fingerprint: 7A2E 0407 C9A6 CAF6 2B9F 8422 C063 5EBB FE1D 66D1