Can I set a different max attachment size based on where the email send / received from. I would like it so internal emails, within the domain, can not be as larger as emails being sent to and from other domains.
My logic is that I would like the email sever to not be used for file sharing as much. But I would still like people to be able to send/receive larger files via email from outside clients.
Is this possible with Exchange 2003?
Short answer: no.
Long answer:
You can set message size limits in four places: globally, on Internet connectors, on virtual SMTP servers and per-recipient.
Per-recipient settings apply to all messages sent or received from that recipient, so they're not going to help you here.
Global limits apply to every message that flows through Exchange, so they will be applied to internal and external ones.
Limits on Internet connectors apply only to messages going out of your organization.
Limits on virtual SMTP servers apply to every message that goes through that virtual server.
The only way to limit message sizes for internal messages is to set global limits or per-recipient limits, because those messages don't go through Internet connectors and/or virtual SMTP servers (unless moving from one Exchange server to another). But if you set global or per-recipient limits, they will apply to external messages, too.
You can get the opposite of what you want: allow larger internal messages and smaller external ones (and this is the usual setup); but you can't have larger limits on external messages and smaller limits on internal ones.
