FortiGate
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.
mle2802
Staff
Staff
Article Id 421204
Description

This article explains how to troubleshoot error code '-155' that occurs when uploading a CA certificate to FortiGate.

The issue is caused by a mismatch between the system time and the certificate’s validity start time.

Scope FortiGate.
Solution When uploading a CA certificate to FortiGate, an error '-155' may occur in certain scenarios.

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This issue occurs because the FortiGate system time is behind the certificate’s validity start time.


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To resolve the issue, make sure the certificate's validity start time is either behind or same as FortiGate's System Time.
 
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Another solution is to modify the system time on FortiGate. Navigate under System -> Settings and manually set the system time.

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