Unable to establish a vpnc connection with Network Manager after upgrade to natty from maverick

I'm using OpenVPN quite happily on natty (also an ungrade from maverick); will see if I can check the MS variety for you ...

ps - OpenVPN appears to be quicker - although that could be the time of day!

MS version appear to work as well.

I have to use the Network Manager vpnc plugin and that one doesn't work...
I keep getting...

May 4 00:41:39 <host> NetworkManager[1016]: <info> Starting VPN service 'vpnc'...
May 4 00:41:39 <host> NetworkManager[1016]: <info> VPN service 'vpnc' started (org.freedesktop.NetworkManager.vpnc), PID 2547
May 4 00:41:39 <host> NetworkManager[1016]: <info> VPN service 'vpnc' appeared; activating connections
May 4 00:41:39 <host> NetworkManager[1016]: <info> VPN plugin state changed: 1
May 4 00:41:39 <host> NetworkManager[1016]: <info> VPN plugin state changed: 3
May 4 00:41:39 <host> NetworkManager[1016]: <info> VPN connection 'VPN Connection Name' (Connect) reply received.
May 4 00:41:39 <host> NetworkManager[1016]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/tun0, iface: tun0)
May 4 00:41:39 <host> NetworkManager[1016]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/tun0, iface: tun0): no ifupdown configuration found.
May 4 00:41:54 <host> avahi-daemon[1007]: Withdrawing workstation service for tun0.
May 4 00:41:54 <host> NetworkManager[1016]: SCPlugin-Ifupdown: devices removed (path: /sys/devices/virtual/net/tun0, iface: tun0)
May 4 00:41:54 <host> NetworkManager[1016]: <warn> VPN plugin failed: 1
May 4 00:41:54 <host> NetworkManager[1016]: <info> VPN plugin state changed: 6
May 4 00:41:54 <host> NetworkManager[1016]: <info> VPN plugin state change reason: 0
May 4 00:41:54 <host> NetworkManager[1016]: <warn> error disconnecting VPN: Could not process the request because no VPN connection was active.
May 4 00:41:54 <host> NetworkManager[1016]: <info> Policy set 'wifinetwork' (wlan0) as default for IPv4 routing and DNS.
May 4 00:41:59 <host> NetworkManager[1016]: <info> VPN service 'vpnc' disappeared

Connecting using the vpnconnect command and then disconnecting using vpndisconnect...

May 4 00:53:47 <host> NetworkManager[1016]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/tun0, iface: tun0)
May 4 00:53:47 <host> NetworkManager[1016]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/tun0, iface: tun0): no ifupdown configuration found.
May 4 00:55:45 <host> vpnc[21566]: select: Interrupted system call
May 4 00:55:45 <host> vpnc[21566]: terminated by signal: 15
May 4 00:55:45 <host> avahi-daemon[1007]: Withdrawing workstation service for tun0.
May 4 00:55:45 <host> NetworkManager[1016]: SCPlugin-Ifupdown: devices removed (path: /sys/devices/virtual/net/tun0, iface: tun0)

Obviously, in the latter case I can use the connection between vpnconnect and vpndisconnect, while in the first case, using the Network Manager interface, I'm getting VPN Connection failed...

Regards.
nP

Double-check your VPN settings. I had the same issue, and picked out the "no ifupdown configuration found" message as a possible reason - after poking for 30 minutes, it turns out I had bumped something (damn trackpad!) and had switched my DH group from 2 to 5. The vpn error reporting for NetworkManager is really opaque...

What does "DH group" mean? Thanks. I'm getting something similar. My bug is over at https://bugs.launchpad.net/ubuntu/+source/network-manager-vpnc/+bug/1207918 .