Complete these steps in order to open secure access to the VPN Concentrator
Select Configuration > Interfaces. Ensure that the public filter is on the public interface and the private filter is on the private interface.
Select Configuration > Policy Management > Traffic Management > Filters. Choose the public filter and click Assign Rules to Filter. Under Available Rules, select Incoming HTTPS In (forward/in) and click Add. Then select Incoming HTTPS Out (forward/out) and click Add.
Select Configuration > Tunneling and Security > SSL > HTTPS and ensure that HTTPS is enabled as this window shows
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