I configured a VPN connection (native Windows PPTP connection) between my home PC (Windows XP Professional) and my office VPN server (Windows 2000 Server). I connect to the Internet via a Cisco 827-4V router (IOS 12.2(8)T4) and my ISP assigns to it a dynamic IP.
When I try to establish the connection it says "Verifying Username and Password" for 40 secs. and then I receive error 721 (The remote computer is not responding), but if I try again and again (50/60 times) I finally succeed in connecting.
I made the following tests:
1) I tried to substitute the operating system (e.g. Windows 2000, Windows NT 4) -> I succeed in connecting every time.
2) I tried to substitute the Cisco 827-4V with a ZyXEL 645R -> I succeed in connecting every time (also with Windows XP).
So, it seems to be a problem with the couple 827-4V / Windows XP, but I really can't understand which problem.
This is my router configuration:
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
enable secret <password>
clock timezone CET 1
clock summer-time CEST recurring last Sun Mar 2:00 last Sun Oct 3:00
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
ip domain-name <domain name>
ip name-server <primary dns server>
ip name-server <secondary dns server>
ip dhcp excluded-address 192.168.30.1
ip dhcp pool Client
network 192.168.30.0 255.255.255.0
dns-server <primary dns server> <secondary dns server>
domain-name <domain name>
ip address 192.168.30.1 255.255.255.0
ip nat inside
ip tcp adjust-mss 1452
hold-queue 100 out
no ip address
no atm ilmi-keepalive
pppoe-client dial-pool-number 1
dsl operating-mode auto
ip address negotiated
ip nat outside
dialer pool 1
ppp pap sent-username <username> password <password>
ip nat inside source list 101 interface Dialer0 overload
ip route 0.0.0.0 0.0.0.0 Dialer0
no ip http server
ip pim bidir-enable
access-list 101 permit ip 192.168.30.0 0.0.0.255 any
dialer-list 1 protocol ip list 101
line con 0
line vty 0 4
access-class 101 in
scheduler max-task-time 5000
sntp server <sntp server>
Does anybody know how to solve the problem.