It can happen if you are using manual VPN connection and trying to connect to any Juniper VPN server from any Windows XP machine. Your system may behave quite normal, everything seems perfect but still you are not able to connect to VPN server. After restarting sometime the system gives the chance to connect to the VPN server and sometimes still remain the same problem.
The solution of this problem is very simple but before that I would like to share the cause of this problem. This problem occur when the respective service of NetScreen crashes but did not change the status of the service to stopped. You just need to find that service in the service panel and restart it. The name of the service is given as under:
Restart SafeNet IKE Service and reconnect the VPN. Its done, now you can easily connect to the VPN server and use the services.