Remote Server returned '550 5.7.1 Message rejected due to unacceptable atta
Delivery has failed to these recipients or groups:
Your message was not due to a permission or security issue. It may have been rejected by a moderator, the address may only accept email from certain senders, or another restriction may be preventing delivery.
Remote Server returned '550 5.7.1 Message rejected due to unacceptable attachments'
I was reviewing this information to validate if it was only to remove an extension so that the filter in the EDGE Transport service would omit it. However, apparently it is filtering by content type and not by extension.
1.- I applied this solution without positive result: https://support.microsoft.com/en-sg/help/945046/you-receive-an-ndr-message-when-you-send-an-e-mail-message-by-using-an
2.- I configured the domain as BypassSenderDomains adding the webex.com domains, etc without positive result. Ref: http://woshub.com/manage-domains-and-email-address-whitelist-in-exchange-server-2013/
What I want is to be able to keep the EDGE side filter enabled so that it can allow the delivery of that webex invitation.