Ubuntu下由於內核更新，出現錯誤提示信息：
Starting /opt/cisco-vpnclient/bin/vpnclient: module directory /lib/modules/2.6.24-21-generic/CiscoVPN not found.
Cisco Systems VPN Client Version 4.8.00 (0490)
Copyright (C) 1998-2005 Cisco Systems, Inc. All Rights Reserved.
Client Type(s): Linux
Running on: Linux 2.6.24-21-generic #1 SMP Tue Aug 12 13:37:22 UTC 2008 i686
Config file directory: /etc/opt/cisco-vpnclient
Could not attach to driver. Is kernel module loaded?
The application was unable to communicate with the VPN sub-system.
解決方法：
找到當前內核之前的舊版本內核，將此舊內核文件夾內的CisoVPN文件夾復制到當前內核版本的文件夾中，如：
舊內核版本：2.6.24-20-generic
當前內核版本：2.6.24-21-generic
進入/lib/modules
#cp -r ./2.6.24-20-generic/CiscoVPN/ ./2.6.24-21-generic/
