Inbound emails from GMail undeliverable only to Fortimail

[dmangual]

There are several gmail accounts that send emails to our organization but just won't come in the inbox. The sender then gets a mail delivery failure error on Gmail. We did some tests from other gamil accounts and the mails get in without a problem. Its like as if Fortimail has blacklisted those accounts. Diagnostic-Code: smtp; 554 5.3.0 connection not allowed

[Bromont_FTNT]

Probably GeoIP blocking... some of the Gmail servers come from IPs that Fortinet has determined as from the  Netherlands or Germany (based on ping times rather than country the IP is registered in)