Technical Tip: Certificate shows invalid status due to FortiGate incorrect system time

[tpatel]

Description	This article describes how to resolve the invalid status error for a certificate that occurs when the FortiGate system time is incorrect.
Scope	FortiGate.
Solution	On the FortiGate, under System -> Certificates. Several certificate shows an invalid status even with seemingly valid 'From' and 'Expires' dates. Inspecting the configuration through the CLI also shows the correct 'Valid From' and 'Valid to' dates. get vpn certificate local details == [ Fortinet_GUI_Server ] Name: Fortinet_GUI_Server Subject: C = US, ST = California, L = Sunnyvale, O = Fortinet Ltd., OU = FortiGate, CN = FortiGate Issuer: C = US, ST = California, L = Sunnyvale, O = Fortinet, OU = Certificate Authority, CN = FGVMULTM25000090, emailAddress = support@fortinet.com Valid from: 2025-10-17 15:45:39 GMT Valid to: 2028-01-20 15:45:39 GMT Fingerprint: 6A:A8:E0:A7:1D:08:46:B7:8E:05:8E:CF:AF:CB:DF:4E:B8:69:F0:47:4E:A5:B4:C6:46:0B:ED:8C:D8:B7:92:3D Serial Num: 7f:0e:d3:f1:a3:a4:75:cc This certificate error could appear on the FortiGate because the date on the device is incorrect, leading FortiOS to think that the certificates are outside of their validity period. execute date current date is: 2000-11-19 To resolve this, check that the date and time on the FortiGate are correct. If the system time is configured manually, it must be corrected. If the FortiGate is receiving time from an NTP server, ensure that the FortiGate can connect to the NTP server and obtain the correct date and time. Related article:  Troubleshooting Tip: NTP synchronization issue