I encountered a very frustrating problem when using CISCO’s Anyconnect VPN client on linux (ubuntu to be specific). Every now and then the client would throw an error right after a successful login:
The VPN client agent SSL engine encountered an error. Please restart your computer or device, then try again. If the issue persists, please contact your network administrator
The client would then exist. Normally, a re-install would solve the problem, however this time it didn’t make any difference. After some troubleshooting, in my case the problem turned out to be a (somehow) corrupted AnyConnect profile. AnyConnect profiles are stored as .xml files in the cisco install folder. So I proceeded to delete my profile’s xml file (in my case called “sysadmins.xml”):
rm /opt/cisco/vpn/profile/sysadmins.xml
The path may be different on your system, either search for “cisco” or search for the xml file itself. The connection profile XML file will have the same name as the group you select when connecting to your ASA
Update: the above only worked for a short while… cisco’s AnyConnect kept on giving me grief with the same errors…. so I hunted around for an alternative and found this to work really well:
David Vassallo's Blog 