Here is a workaround to use a VPN in combination with FortiClient.
- Retrieve the Fortinet tools from Fortinet ex: FortiClientTools_7.0.2.0090.
You must keep your FortiClient installed.
- Copy this directory to a directory on your computer.
- Enable Forticlient VPN / SSL in Tools - Add-on Manager
- In an RDP entry Properties go to Connection - VPN/SSH/GATEWAY
- Change the VPN Type for FortiClient VPN / SSL
- Click the Settings (FortiClient VPN / SSL) tab.
- Change the Connection mode for FortiSSL
- Configure your tunnel and click OK
- Launch the connection for your RDP entry.
On the first connection it will ask for the path of the FortiClient tools you have saved on your computer.