We have problems in receiving emails with attachments from several domains.
We are using Cisco PIX515E with OS ver 7.2. We have three public MX records and configure the firewall to forward emails to three anti-spam box running GFI as SMTP smarthost and the final destination is our Exchange 2003 server.
When I look at the queue from all three smarthosts, I can see the email sitting in the queue and when I tried to open the attachment, it is incomplete. What happened next is that this email will sit there until the SMTP timeout and the sender will receive a bounce back saying message timeout and will try to deliver again. It will keep going on and on until the server on the other end gave up.
I have contact GFI and verified that their product only work after entire message has been received. Therefore, it is not the antispam. I also tried to disable the "inspect smtp" on the firewall and upgraded it from 7.0 to 7.2.
All three smarthosts will have the same result after they receive emails from these domains, i.e. emails with incomplete attachments.
I am running out of ideas now and hope there is a suggestion here.