Message submission

The University's message submission service is provided by smtp.ox.ac.uk and 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 University's central VPN service to tunnel back to the Oxford network so that you can connect to smtp.ox.ac.uk.

  • Anonymous

Only available to Oxford University IP addresses.

 

Limits apply to how much mail an individual user or host can send via smtp.ox.ac.uk.  IT support staff (ITSS) can submit a service request to apply for frequent heavy users/hosts to have an increased limit.

ITSS are able to view the existing lists of exemptions at the links provided in the posting to ITSS-Announce on 22 June 2020.

The maximum message size accepted is 100 Mbytes.

Alternatively, you may choose to use the message submission service provided by Nexus365.

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.

Permanent errors result in an SMTP 5xx error code.

Temporary errors result in an SMTP 4xx error code.  Depending on your client's SMTP implementation, it may automatically retry after a temporary error.

Expand All

HST-BAN: Sending host blacklisted [permanent error]

Explanation

The sending host is blacklisted.

Solution

For further details please contact the Service Desk with the subject My host's IP address is banned from sending to smtp.ox.ac.uk.

HST-FLD: $sender_host_address is sending too quickly. Please try again later. [temporary error]

Explanation

You have not authenticated and you are sending at a rate higher than your host's allowance.

Solution

Speak to your local IT support staff and ask them to submit an OSM Service Request to have your host's allowance increased.

RLY-OPN: Open relay not permitted [permanent error]

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.

USR-FLD: $authenticated_id is sending too quickly. Please try again later. [temporary error]

Explanation

You have authenticated and are sending at a rate higher than your allowance.

Solution

Speak to your local IT support staff and ask them to submit a service request to have your allowance increased.

Get support


Local IT support provide your first line of on-the-spot help

FIND MY LOCAL IT TEAM

 

Common requests and fault reports can be logged using self-service

   USE IT SELF-SERVICE    

   LOG A SUPPORT CALL    

VIEW MY SUPPORT CALLS  

The central Service Desk is available 24x7 on +44 1865 6 12345

 

If you do not have an SSO account you can use this form to contact the Service Desk