I have a Fortigate that recently upgraded from 7.2.13 to 7.4.12, according to Fortinet this is a valid upgrade path. After the upgrade SSLVPN which was working before no longer works. Forticlient gets to 45 percent and then disconnects. Connection from the Fortigate to the server works. Rolled back to 7.2.13 and SSLVPN works again. Any ideas?
Ran into an issue yesterday, 3 FortiAPs managed in the cloud was randomly disconnecting wireless devices only on one SSID. Verified dns and network settings received from DHCP were fine. Verified we were getting proper power from the switch, also Fortiswitch and Fortigate was not in conserve mode. Verified outbound traffic was being allowed as well. After everything was rebooted I upgraded the 3 FortiAP firmware from 7.4.5 to version 7.4.6, once the upgrade was done wireless devices on the SSID in question are working again. Also verified the AP power/signal settings were within a good distance range. Weird issue but its resolved now.
TLDR: FortiAP on 7.4.5 causes random disconnects for wireless clients, upgrade to FortiAPOS 7.4.6