hi,
i have setup a hybrid to migrate to office 365 with centralized mail flow. But we are unable to recevie an email from office 365 mailbox to on-prem server for internal and external emails. we have opened our firewall for 25 port from anywhere over the internet and we are not seeing any traffic coming in on FW.
i am little confused with the current environment.
we have a domain (abc.com - MX record) where all the external emails come in and go out.
we have a owa, ews, autodiscover (owa.abc.com) for external access/URL.
From where exactly we have to open 25 - abc.com or owa.abc.com.
if we give FQDN in HCW as Abc.com then there is a email comng to on-prem exchange from office 365 for internal mailboxes, but if the email is sent to external like gmail.com or outlook.com it is failing with the error.
Error : 550 5.7.367 Remote server returned not permitted to relay -> 550 Relaying denied.
Thanks
Pavan.