Since 18 months i use Fortiauthenticator 6.01 without trouble but since few days Fortiauthenticator can't send email with Office365.
I open a ticket but at this time no solution to fix it.
The error message is :
"smtp starttls: verify peer certificate: unable to get local issuer certificate"
and the second:
"smtp mail: failed send to email@example.com via smtp.office365.com:587"
I deleted certificate Office365 and i created a new but no good result.
To create certificate i exported root certificate X.509 Base 64.cer and i exported intermediate certificate in the same format. I created a new text file and i put root certificate and intermediate certificate inside the text file.
I imported in fortiauthenticator.
I try another method for certificate, import directly root certificate and second step import directly intermediate certificate. Same trouble.
I don't understand where is the problem and i don't understand why the error message speak about "unable to get local issuer certificate" why Local ? in my brain i think it's a remote certificate.
Thank you for your help and sorry for my english :)
it might happened that office365 change their certs and/or even root CA.
I'm not sure at the moment. But it has then nothing to do with FAC (FortiAuthenticator) as that could not be foreseen on FAC side.
I would suggest to follow those steps to check situation:
1. check certs of office365 via attempt to open STARTTLS conenction :