In Windows Application log appears error 1722 (MsiInstaller) - problem with vpnva-6.inf:
1. Uninstall previous version of Cisco AnyConnect (if any)
2. Open cmd.exe as administrator
3. List drivers in system: pnputil -e
4. Locate any drivers from Cisco Company and remove them with command:
pnputil -d oemXX.inf (XX is number of inf file)
5. Restart PC
6. Install Cisco AnyConnect again