None of the users on our domain are able to receive emails with attachments. Text-only emails go through with no problem, but we cannot receive any messages with attachments, even internally. No NDR or any other error message comes up, they seem to just disappear.
We are running Exchange 2007 on an SBS 2008 server. I have not changed any configuration options at all recently, and the setup is mostly default settings. I have tried looking for any settings regarding attachment handling, but have not had a great deal of experience in the deeper parts of Exchange.
How can these messages be disappearing without even an error to the sender that it didn't go through?