Sorry , i mean "Import local certificate is invalid"
I have also followed the instructions below to import certificate
Import the signed certificate into your FortiGate device
1. Unzip the file downloaded from the CA.
There should be two .CRT files: a CA certificate with bundle in the file
name, and a local certificate.
2. Log in to your FortiGate unit and browse to System > Certificates.
3. Select Import > Local Certificate to import the local certificate.
The status of the certificate will change from PENDING to OK.
4. Import the CA certificate by selecting Import > CA Certificate. It will be
listed in the CA Certificates section of the certificates list.
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