Just a quick heads up, as this caught me out today. I am not even sure if this is the case in SP1 for exchange and I have no time to check, but it is in Exchange SP2.
If you are running GFI MailEssentials 11 on your Exchange server, and are using the List Server element of this great application, make sure to uncheck this highlighted box! If you don’t, your lists will not work from external addresses. (MailEssentials will still filter using the directory harvesting option).
That’s too bad for you folks running GFI – That check box helps reduce the amount of NDR’s your exchange server needs to send. That box should have been checked in exchange years ago!!
No, its not too bad… because we have directory harvesting checks which do exactly the same thing.
It is simply better for you guys without GFI 😉