Hello There,

Could you guys Help me?

We have an external app hosted on a vendor Webserver. They need to send e-mails to our Exchange Environment, authenticating the e-mail.

To allow that, I understand that:

1 - I need to create a receive connector

2 - Scope the Receive connector to the External IP Address of the vendor's website

3 - Configure the Exchange User authentication mode.

Is that correct? I know that some applications need to allow the Anonymoys Authentication checkbox and also allow the relay through the Add-Adpermission cmdlet, but I guess that this is not the case. The application has a secure Method and uses a username and password that we created. Or Am I understanding this incorrectly? All e-mails that users send using another applications that not Outlook, ActiveSync of OWA are automatically classified as "Anonymous" even if they use a Username, Password?
The Application uses the New System.Net.Mail.MailAddress method on Visual Studio.

And, if you guys can answer another quick question that I cannot find the answer, it would be great: IF I have a load balanced solution for my CAS servers and create a receive connector in just One server, will the sender bounce if the connection is balanced to another CAS that does not have the receive connector?

THANKS!

Hello

tip: enable verbose logging on connector. check Authentication setting on connector.
you need create on all CAS server the receive connector with same settings.

Hi,

According to your post, I understand that you want to allow external application send message to Exchange server.
If I misunderstand your concern, please do not hesitate to let me know.

We need create an receive connector to relay mail flow as you mentioned, for your reference(same as Exchange 2013):
https://technet.microsoft.com/en-us/library/bb232021%28v=exchg.141%29.aspx?f=255&MSPPError=-2147217396

For second question, we need same configuration in all CAS server as Sneff_Gabor provide.

Thanks