Periodically your VPN Client (FortiClient) will need updated. In most cases uninstalling the old one is needed first. Follow these steps to uninstall and click the link at the bottom to download and update your client.
Uninstalling
Windows
Click Start
Type “add remove”
Select “Add or Remove Programs”
Scroll down until you see “Forticlient”
Select “Forticlient” and click “Uninstall”
Follow the Uninstall process
At the end it will ask to restart your computer, click the restart option to restart immediately
Follow the link below to install the latest supported Forticlient version and follow the install instructions
Mac/Apple
Open Finder
Click “Applications” on the left-hand side
Scroll until you find “FortiClientUninstaller” and double-click it
Follow the Uninstall process
Reboot your computer
Downloading, Reinstalling, Configuring
Follow the instructions found in this article for step-by-step instructions to install and configure the VPN client.