Trouble configuring a VPN interface to access a Windows network

[Kevin Gilbert <kmg952 bigpond com>]

I am having trouble configuring a VPN interface to access a Windows network.

Within the Windows "Network Connections" window this connection is listed as:
Name: <net name>
Type: Virtual Private Network
Device Name: WAN Miniport (PPTP)

It was created via the "New Connection Wizard" as follows:
Network Connection Type: Connect to the network at my workplace
Network Connection: Virtual Private Network connection
Connection Name: <net name>
Public Network: Do not dial the initial connection
VPN Server Selection: <host name / ip address>
Connection Availability: Anyone's use

I have tried to configure the connection via the nm-applet as follows:
Choose a VPN Connection Type: Point-To-Point Tunneling Protocol (PPTP)
Gateway: <host name / ip address>
User name: <user name - see Note>
Password: <password - see Note>
NT Domain: <domain name - see Note>
(Advanced Button - basically used the defaults)
Authentication
    Allow the following authentication methods: (all checked)
Security and Compression
    Use Point-To-Point encryption (MPPE): unchecked
    Allow BSD compression: checked
    Allow Deflate compression: checked
    Use TCP header compression: checked
Echo
    Send PPP echo packets: unchecked

NOTE: The user name, password are those that are entered in Windows when the I 
connect to the VPN and the Domain is the Windows domain that I am logging 
into. Note that the user name and password used for the actual Windows login 
is different to the ones used above.

When trying to activate the connection, the following is produced in the 
system log file. (Note that this has been slightly edited for security 
reasons.)

NetworkManager: <info>  Starting VPN service 
'org.freedesktop.NetworkManager.pptp'...
NetworkManager: <info>  VPN service 'org.freedesktop.NetworkManager.pptp' 
started (org.freedesktop.NetworkManager.pptp), PID 25013
NetworkManager: <info>  VPN service 'org.freedesktop.NetworkManager.pptp' just 
appeared, activating connections
NetworkManager: <info>  VPN plugin state changed: 3
NetworkManager: <info>  VPN connection 'VPN connection 1' (Connect) reply 
received.
pppd[25016]: Plugin /usr/lib/pppd/2.4.4/nm-pptp-pppd-plugin.so loaded.
pppd[25016]: pppd 2.4.4 started by root, uid 0
pppd[25016]: Using interface ppp0
pppd[25016]: Connect: ppp0 <--> /dev/pts/2
pptp[25017]: nm-pptp-service-25013 log[main:pptp.c:314]: The synchronous pptp 
option is NOT activated
pptp[25026]: nm-pptp-service-25013 log[ctrlp_rep:pptp_ctrl.c:251]: Sent 
control packet type is 1 'Start-Control-Connection-Request'
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:739]: Received 
Start Control Connection Reply
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:773]: Client 
connection established.
pptp[25026]: nm-pptp-service-25013 log[ctrlp_rep:pptp_ctrl.c:251]: Sent 
control packet type is 7 'Outgoing-Call-Request'
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:858]: Received 
Outgoing Call Reply.
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:897]: Outgoing 
call established (call ID 0, peer's call ID 61490).
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:950]: 
PPTP_SET_LINK_INFO received from peer_callid 50110
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:953]:   
send_accm is 00000000, recv_accm is FFFFFFFF
pptp[25026]: nm-pptp-service-25013 warn[ctrlp_disp:pptp_ctrl.c:956]: Non-zero 
Async Control Character Maps are notsupported!
pppd[25016]: CHAP authentication succeeded
pppd[25016]: LCP terminated by peer (^BM-?-M-K^@<M-Mt^ ^@^BM-f)
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:950]: 
PPTP_SET_LINK_INFO received from peer_callid 50110
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:953]:   
send_accm is FFFFFFFF, recv_accm is FFFFFFFF
pptp[25026]: nm-pptp-service-25013 warn[ctrlp_disp:pptp_ctrl.c:956]: Non-zero 
Async Control Character Maps are notsupported!
pptp[25026]: nm-pptp-service-25013 log[ctrlp_disp:pptp_ctrl.c:912]: Received 
Call Clear Request.
NetworkManager: <info>  VPN plugin failed: 1
pppd[25016]: Connection terminated.
pptp[25017]: nm-pptp-service-25013 warn[decaps_hdlc:pptp_gre.c:204]: short 
read (-1): Input/output error
pptp[25017]: nm-pptp-service-25013 warn[decaps_hdlc:pptp_gre.c:216]: pppd may 
have shutdown, see pppd log
pptp[25026]: nm-pptp-service-25013 log[callmgr_main:pptp_callmgr.c:234]: 
Closing connection (unhandled)
pptp[25026]: nm-pptp-service-25013 log[ctrlp_rep:pptp_ctrl.c:251]: Sent 
control packet type is 12 'Call-Clear-Request'
NetworkManager: <info>  VPN plugin failed: 1
pptp[25026]: nm-pptp-service-25013 log[call_callback:pptp_callmgr.c:79]: 
Closing connection (call state)
pppd[25016]: Modem hangup
pppd[25016]: Exit.
NetworkManager: <info>  VPN plugin failed: 1
NetworkManager: <info>  VPN plugin state changed: 6
NetworkManager: <info>  VPN plugin state change reason: 0
NetworkManager: <WARN>  connection_state_changed(): Could not process the 
request because no VPN connection was active.
NetworkManager: <info>  Policy set 'Auto xxxxxxx' (wlan0) as default for 
routing and DNS.

I have been able to get other VPN connections to work - its just this one.

Thx in advance for any help,
Kevin