FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
Check if the admin-server-cert settings have the right certificate with hash above SHA-1 (which is not supported anymore).
Starting in FortiOS v7.2.5, users should use the built-in Fortinet_Factory certificate, or SHA-256 and higher certificates for the web management interface.
For example:
config system global
set admin-server-cert Fortinet_Factory
end
SHA1 would not be supported anymore from v7.2.5 onwards.
