I have a 4 pc peer to peer network. We have a verizon DSL along with a linksys 4 port Linksys DSL Router. We are all on windows xp pro and are all using outlook express. we are able to send and receive email fine but we are unable to send attachments. I set norton to not scan outgoing messages and we do not have any type of firewall installed. If you have any ideas please let me know.