Mail received via BCC is not being forwarded

[Robert_Spokane]

We have an O365 mailbox that forwards to an external customer. Forwarding works in all cases except for when the O365 mailbox receives a mail via bcc, in which case it does not forward that mail.

Any suggestions?

Edit: I've looked at all the filters for mail flow and none of them will look at the bcc field, which makes sense I suppose, but why isn't there a forwarding rule that just says "Everything that enters this mailbox gets forwarded." 

[#2]

Hi Robert,

You can create a rule in OWA (https://outlook.office365.com/owa) as below, to redirect all emails to a contact :-

Alternatively you can create a mail contact for the external recipient in ECP and then create a transport rule to forward all emails for that shared mailbox to external recipient.

Deepak

[#3]

@DeepakRandhawa   Thank you for the reply. We have a general forwarding rule in place. Everything received is getting forwarded properly unless the mail was received via bcc in which case it does not get forwarded.

[#4]

Is your general forwarding rule something like the screenshot i have shared. It should, in theory, forward all messages coming to mailbox.
You can also use flow, though I'm not sure about licence requirements for it, if there are any.