Message Submission

IT Services

Message Submission

Contents

1. Explanations of our error messages
2. Statistics

The University's message submission service is provided by smtp.ox.ac.uk .

The service can be accessed on either port 587/tcp (recommended) or 25/tcp. There are two types of access.

Authenticated: SMTP AUTH is available globally and offers GSSAPI, LOGIN and PLAIN authentication types. Use port 587 because many ISPs block outbound 25/tcp traffic. It is unlikely the network you are on will block port 587 but in the event that it does, use the OUCS VPN service to tunnel back to the Oxford network so that you can connect to smtp.ox.ac.uk.
Anonymous: Only available to Oxford IP addresses.

Details of how to set up a secure connection to Oxford are given in the setup instructions for individual email clients.

ICTC Regulations require Oxford hosts to be registered in the DNS. Those that are not are denied service.

The maximum message size accepted is 100 Mbytes.

1. Explanations of our error messages

Here is a list of error messages given by the University message submission service.

Words beginning with $ are variables which are substituted with applicable values in each message.

1.1. DAT-CLM: Message contains malware ($malware_name)

Explanation

Message contains malware.

The name Oversized.Foo means that an archive of format Foo had too high a compression ratio (currently limited to 300:1).

Solution

Remove the malware.

For Oversized.Foo you can try one of the following

Reduce the compression ratio to below 300:1
Encrypt the archive to prevent unpacking
Use a protocol designed for file transfer (SMTP wasn't)

1.2. HST-BAN: Sending host blacklisted

Explanation

The sending host is blacklisted.

Solution

1.3. HST-PTR: Oxford host has no PTR record

Explanation

The Oxford sending host has no PTR record in the DNS. This is a contravention of ICTC Regulations.

Solution

Contact your local IT staff and get your host registered.

1.4. RLY-OPN: Open relay not permitted

Explanation

You are attempting to use smtp.ox.ac.uk as an open relay.

Solution

The reason for this is because you are not using a computer with an Oxford IP address and you are not authenticating yourself. You should configure your email client to use authentication.

1.5. SND-VFY: Sender domain verification failed

Explanation

The sender domain is not correctly registered in the DNS. The sender address must be correct so that you can be notified of any delivery errors.

Solution

Make sure that the sender address configured in your email client is correct.

2. Statistics

Some message submission statistics are available.