Prioritizing SMTP out traffic in ISA server

Hello experts,
We have an Exchange 2003 server in an internal network which is behind an ISA server.

ISA is connected to the internet through an ADSL 512DL/256UL connection.

Because of the low bandwidth of upstream (256kbps), when some exchange user is trying to send an email message more than 1MB, the message is being delayed for many hours and maybe days.

The question:

How to give exchange server SMTP outbound traffic a priority over other traffic in ISA server?
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Stephen MandersonSoftware EngineerCommented:
Few questions..  What version of ISA are you using? Doesn't sound like this is an ISA issue as such, what is the upload times of such files, to say a web server? Are these emails sitting in the queue? What else is the connection being used for? Do you have offsite backup?

ISA doesnt provide traffic shaping services by default so it cannot prioritise out of the box, you'll require 3rd party software for this.

I presume that there only a few users with a connection like that, take a look at bandwith splitter, It offers a full service up to 10 users;

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Keith AlabasterEnterprise ArchitectCommented:
Agreed - ISA is not interested in traffic prioritisation or QOS.
Stephen MandersonSoftware EngineerCommented:
Hows things Keith? Done with uni and back to dabbling with forefront.. Think I've been out too long ha.
Keith AlabasterEnterprise ArchitectCommented:
lol - welcome back :)
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