Hi
Can you try running the following command:
sudo /opt/cisco/vpn/bin/vpn_uninstall.sh
If not you'll need to remove your application (drop it to your trash bin) and remove all the following folders (don't remember if this is valid for version 3.1):
rm -rf /System/Library/StartupItems/CiscoVPN
rm -rf /Library/StartupItems/CiscoVPN
rm -rf /System/Library/Extensions/CiscoVPN.kext
rm -rf /Library/Extensions/CiscoVPN.kext
rm -rf /Library/Receipts/vpnclient-kext.pkg
rm -rf /Library/Receipts/vpnclient-startup.pkg
Thanks
Francesco
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