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You can download the full installer from our support site (support.fortinet.com).

After logging in, hover over Download and select Firmware Images. Then use the dropdown to select FortiClient and adjust the red box below from Release Notes to Download. From here you can navigate the directories to find the version you wish.

Případně by mělo by fungovat toto:

You can find the full installer on "C:\Users\<your_user_name>\AppData\Local\Temp" after completing download of Forti Client Online Installer which are FortiClientVPN.exe