Recipient filtering

Question

Hello!

I've enabled Recipient filtering on my MBX servers for both external and internal recipients and added the recovery mailbox to the block list

...but messages still being delivered to this mailbox. Am I missing here anything?

Thank you in advance,
Michael

Answer 1

haha. True, but that article doesnt mention how to configure it though :)
The config article is for the Edge Role:
https://learn.microsoft.com/en-us/exchange/antispam-and-antimalware/antispam-protection/recipient-filtering?view=exchserver-2019

I suspect that since its really intended for the Edge role, they didnt want to take the time to create a different install package for just the mailbox servers and decided to just put that warning in the article instead. :)

Answer 2

Yea, I dont think that works as expected and shouldnt be enabled:
https://learn.microsoft.com/en-us/exchange/antispam-and-antimalware/antispam-protection/recipient-filtering?view=exchserver-2019
https://learn.microsoft.com/en-us/exchange/antispam-and-antimalware/antispam-protection/antispam-on-mailbox-servers?view=exchserver-2019

Answer 3

Ha, but exactly this article -

https://learn.microsoft.com/en-us/exchange/antispam-and-antimalware/antispam-protection/antispam-on-mailbox-servers?view=exchserver-2019

• describes the process of enabling Recipient Filter on MBX servers! Why would MS publish it should it not work at all? ...at least theoretically...

When I'm sending mail to the mailbox.recover@Company portal .net I do see these messages in the spam log:

...but they seem to be the subject only to Content Filtering, not the Recipient Filtering.

If it really can't work as described in the MS article... no comments :(((

Answer 4

"True, but that article doesnt mention how to configure it though :)" - yes, you're right, but my text book says that

Recipient filtering is enabled by default, but does not have any lists or providers configured.
To view the current configuration, use the Get-RecipientFilterConfig cmdlet. To enable the
block list, run the following command:
Set-RecipientFilterConfig -BlockListEnabled $true

and according to this it looks as if it were really working:

Anyhow, when I see a warning in the documentation I'm taking it just as the warning and not as something like... the statement "Don't ever try to do it because we just don't want to admit this feature is not working."

:(((

Thank you for the help, AndyDavid!

Regards,
Michael