Cisco VPN Error #404 -
"The Remote Peer terminated the connection during the negotiation of security policies. "
Explanation: These error usually means that the security (IKE) negotiations between your VPN clientand the VPN server failed for any variety of reasons (hence vague error message).. Usually this is because of a timeout, which can be caused by bandwidth issues, ISP issues, latency on the connection... Suggestion, reboot, grab a coffee and try it again.. If it persits.. talk to your VPN admin and have him check the logs for the times you attempted to connect and see if there is anything in the logs to indicate the failed connections.
Biggest culprits, poor ISP of yours, on poor Wi-Fi wireless, poor ISP connected to the company's VPN or conflicting apps (eg: multiple security apps interfering with VPN/tcp ports) on laptop.