skip to content

IT Help and Support

University Information Services

Editing the list configuration

Options found under Admin -> Edit List Config

List definition 

  • Subject of the list: a single line summary of the list which appears on lists of lists.
  • Visibility of the list: whether or not the list is publicly visible. Three settings:
  1. no conceal. Visible to anyone searching for lists on People can find the list and attempt to subscribe to it. Useful for society mailing lists.
  2. conceal except from subscribers: Invitation only/private lists which do not want to attract random external subscribers.
  3. conceal even from subscribers (secret). Typically used for large scale distribution lists.

Sending/receiving setup

  • Who can send messages: see list posting policies. Only privileged owners can change this setting.
  • Delivery time (hh:mm): Deliver queued messages at a specific time of day. May be useful for timed announcements.
  • Digest frequency: Specifies specific days of the week that digest messages should be sent, and the time of day. People subscribed to mailing lists who have set their delivery/reception mode to one of "Digest MIME" or "Digest plain text" will typically receive one message a day for the list.
  • Digest maximum number of messages: Automatically send a digest when (for example) 25 messages have been sent to the list in a single day.
  • Available subscription options: reception mode: Defines the allowed reception modes for the list so that digest or non-digest messages can be blocked. list owners will rarely need to change the default value
  • Subscription profile: Reception mode: default reception mode. Typically "standard" or "digest MIME format" although other values are available.
  • Subscription profile:  Visibility: Defines whether Reception mode is shown on the list of subscribers.
  • Reply address: adds a Reply-To: header to the list if responses should be sent to the list or the original sender. The default value of "other email address" with no target provided tells Sympa not to add a Reply-To: header at all, for consistency with the old Mailman system. List owners will normally want to leave this setting alone.
  • Subject tagging: Adds a short piece of text of the form "[tag]" to the subject line of each message sent to the list. Some recipients find this useful.
  • Reject mail from automatic processes (crontab, etc): Blocks messages with specific message headers which indicate automatically generated emails. This should normally be left disabled. A separate setting, 'Regular expression applied to prevent loops with robots', exists to block email loops. This can be found on the Edit List Config -> Miscellaneous page described below.


  • Who can view list information: Is the List Home page visible to people who know the URL of the page? This is separate from List definition -> Visibility of the list which determines if a list can be found by searching from the top page
  • Who can subscribe to the list  and Who can unsubscribe: define whether people are able to subscribe and unsubscribe to the list by themselves. The default is "owners approval" which forces all (un)subscription attempts to be moderated by the list owners.
  • Who can invite people: the default value of "restricted to subscribers" means that only subscribers to the list can invite others. The subscriptions may still need to be approved by the list owners based on the Who can subscribe to the list setting described above.
  • Who can review subscribers: value fixed to as  "only owner (and listmaster)".

The final two options are fixed, and mean that at least one owner of the list must have an email address which ends, to ensure continuity:

  • Required domains for list owners:
  • Minimum owners in required domains: 1 


  • Store distributed messages into archive: defines whether emails sent to the list should be archived. This defaults to "disabled (off)", as many lists do not require archives.
  • Access right: defines who can access the archives (owner/subscribers/anyone)
  • Quota: defines the maximum amount of email which can be archived on this list, defined by the listmaster. May be use to restrict very high volume lists
  • Maximum number of month archived: automatically discard email archives after a certain number of months. Used in combination with quota above
  • Protect web archive against spam harvesters: Various different means to exist to protect email addresses which exist in web archives:
  1. use HTTP cookie (default)
  2. use JavaScript
  3. replace @ characters (with localpart AT domain)
  4. only show gecos ("Firstname Lastname" <address@concealed>)
  5. do nothing (only appropriate when list archives are restricted to list subscribers, owners or listmaster).

The default setting of "use HTTP cookie" is normally appropriate, but does block external search engines such as Google. "replace @ characters" matches the behaviour of the old Mailman system. Changes take effect immediately.


Email addresses don't last indefinitely: staff and students eventually leave the University. This means that over time an increasing collection of invalid addresses accumulate on mailing lists. The UIS has historically cleared out invalid email addresses from mailing lists once a year (typically a week or so after accounts are shut down for final year undergraduates). However Sympa has its own mechanism to track and automatically delete invalid subscriptions.

Each message sent to a Sympa mailing list acquires a return-path address of Bounce messages for invalid mail addresses (also known as as Mail Delivery Reports) are returned to this email address. 

List owners receive a warning if more than 30% of the subscribers on the list are causing bounces: this is normally an indication of poor data quality.

Email addresses that are having problems are not removed automatically as problems may be transient (for example quota problems or temporary problems with mail systems) rather than an indication of a permanent failure. 

Instead, Sympa assigns a bounce score for each address which has problems, based on the number of bounces that have been seen over the last few weeks The bounces page has a number of settings to manage bouncing email addresses based on this score.

Management of bouncers, 1st level : threshold points

Management of bouncers, 2nd level : threshold points

 The following actions are possible at these two thresholds:

  1. remove bouncing users           (default for 2nd level)
  2. send notify to bouncing users  (default value for 1st level)
  3. do nothing                     

Setting both values to "do nothing" disables bounce processing on the list. This is not recommended. Sympa can also optionally send out notification messages when invalid subscribers addresses reach either of the two thresholds:

  1. do nothing           
  2. owner             
  3. listmaster 

Percentage of list members in VERP mode 

It is not always possible to determine the email address which has caused a bounce message, especially when email is forwarded from the original subscriber email address to some other destination. Variable Envelope Return Path (VERP) uses different sender addresses for every member of the list of the from:

rather than:

This allows Sympa to reliably determine the subscriber on the list which is causing bounces. It is however much less efficient as a separate email message is sent to every single subscriber. The return path addresses are also rather ugly, which is an issue as Microsoft clients insist in displaying them.

A low but non-zero VERP percentage (say 2%) should still be good enough to pick up invalid email addresses on a high volume list.

The current state of the bouncing users can be found on the Bounces tab

Data sources setup

The subscribers, owners and moderators for a mailing list are normally added by hand via the Web interface. However is is possible to define additional subscribers, owners and moderators using one or more external data sources in each case.

All of the data sources have two common attributes:

the data source

  • Blue AD (filter on groupName)                     

data source parameters

  •  The name of the group. Typically of the form inst-group-name

Additional options specific to list subscribers defined by this data source:

  • Notify subscribers when they are included from a data source? enabled / disabled 

 Additional options specific to list owners defined by this data source:

  • profile: whether owners defined by this source are privileged or normal owner. Privileged owners are owners who can add further owners to the list.
  • reception mode: whether owners defined by this data source should receive notification messages about the list (e.g. (un)subscriptions, bounce notifications).
  • visibility: whether owners defined by this data source appear on the List Home page menu.               

Additional options specific to list moderators defined by this data source:

  • reception mode: whether moderators defined by this data source should receive notification messages about the list (e.g. (un)subscriptions, bounce notifications) 
  • visibility: whether moderators defined by this data source appear on the List Home page menu.               

Remote file inclusion

It is also possible to include subscribers (and only subscribers, not owners or moderators) from a Web page protected by a username and password and a valid TLS certificate:

At the moment this can only be set up by the Sympa listmaster. Please contact if this is of interest to you.

SOAP Application Programming Interface (API)

Sympa provides a (fairly minimal)  API which allows external scripts authenticated as a list owner to make changes to a list. 

This is described on a separate page

However the data sources covered in this section probably cover most of the existing use cases for people who attempt to update existing Mailman lists using screen scrapping scripts.


DMARC is a means of checking that the From: header in the body of a mail message (the value that most people see in their email clients) has not been forged by a third party. 

The details aren't important here apart from the fact DMARC interacts badly with Mailing List software such as Sympa, which can accept email from people anywhere in the world only to forward the messages on to other people anywhere in the world

The options on this page replace the from: header in the message body with text of the form:

From: <Senders Full Name> (via list-name Mailing List)

List owners should leave this setting alone if anyone posts to their mailing list email eternal email addresses (email addresses which do not end The default setting will have no effect for people posting using addresses

ARC is an experimental technology intended to work around the problems that strict DMARC implementations cause with mailing lists. This is a better long term solution which will be probably be deployed for all mailing lists at some point in the future. It is not something that individual list owners will need to worry about.

List description/home page

You can edit two files files associated with your list:

  • List homepage: HTML text to describe the list. If this is not defined, the plain text om in the following field is used instead
  • List description: appears at the top of the main List Home page, after the sinlge line Subject. Also in response to "INFO list-name" email commands sent to

Message templates

You can edit several messages/files associated with your list:

Automatic messages 

  • Welcome message: This message is sent to new subscribers.
  • Rejection message: when a message is rejected by list moderator, a notification can be sent to the original author. You may prepare various rejection messages.
  • Reminder message: This message is sent to each subscriber when using the command REMIND. It's useful to help people who are confused about their own subscription emails or people who are not able to unsubscribe themselves.
  • Subscribing invitation message: sent to a person if someone uses the INVITE command to invite someone to subscribe.

Added in distributed messages

  • Message footer: If this file is not empty, it is added as a MIME attachment at the end of each message distributed to the list.
  • Message header: If this file is not empty, it is added as a MIME attachment at the beginning of each message distributed to the list. 


  • Unsubscribe message: This message is sent when users leave the list.
  • Deletion message: This message is sent to users when you remove them from the list using the DEL command (unless you select the Quiet option). 
  • Virus infection message: not used by as virus scanner is external.


Two options that can be set:

  • Regular expression applied to prevent loops with robots: stops Mailing List Managers such as Sympa and Mailman from accidentally sending messages to the list.
  • Periodical subscription reminder task: sends messages to list subscribers every few months or once a year.

Most list owners will want to leave these two settings alone.

Privileged list owners will also see some information about the state of list:

  • Creation of the list: who (email address of owner) and date
  • Last update of config: who (email address of owner) and date
  • Status of the list: (open/closed)
  • Serial number of the config (how many times it has been updated).

Remove list

Appears only when you click Admin in the left hand menu (site admins only).

Rename list

Appears only when you click Admin in the left hand menu (privileged  owners only).

The new name of the list will be approved by the listmasters before it takes effect.



Subscribing and unsubscribing members

You can either add a single person (To add an individual user) or a list of people (To add multiple users). In both cases a "quiet" option exists to add people without sending out the welcome message. Click Add or Add subscribers to add the new members to the list.

To unsubscribe people, tick checkbox on the left under Subscriber Table, and then Delete selected email addresses (which becomes available as soon as at least one subscriber is selected on the page). The checkbox at the top of the list of list members can be used to select all subscribers on the page. Again a "quiet" option exists to remove people without sending out the unsubscription message.

Viewing the subscribers list 

Sympa normally breaks the subscriber table into separate pages of 25 subscribers, so that you can navigate back and forth. This number can be increased using "Page Size" under the current page of list members (changes will take effect immediately). it is also possible to search on email address or name (Search for a User), in order to focus in on specific list members that you wish to remove from the list.


This page lists the current owners of your list. Owners are the set of people who can make changes to the configuration of the list. 

Privileged owners can also can remove existing owners, and add new ones. There are a couple of other operations which are restricted to Privileged owners, noted elsewhere on this page.

Each owner defined for the list has a number of options, closely matching the set of options for list moderators described in the next section:

  • privileged owner: Privileged owners can add and remove owners
  • email address 
  • name: typically "Firstname Lastname" or "Initials Lastname". A default value is provided when email address are added.
  • no notifications: whether this owner should receive notification emails, for example: (ub)subscribe, bounce handling events.
  • concealed from list menu: list owners name or email normally appears under Owners at the top left of the List Home page.
  • private information: a brief comment which is only visible to the owners of the list. This might (for example) explain why someone has been added as a list owner.


List moderators approve messages which are sent to the list if they are not automatically allowed by the following setting:

Edit List Configuration -> Sending/receiving setup -> Who can send messages 

If no list moderators are defined the list owners take on this function. If someone needs to be both an owner and a moderator on a list that had moderators defined then they need to be registered as both an owner and a moderator.

This page lists the current moderators of your list. You can remove existing moderators, and add new ones. Each moderator defined for the list has a number of options, closely matching the set of options for list owners described in the previous section.

  • email address 
  • name: typically "Firstname Lastname" or "Initials Lastname". A default value is provided when email address is added.
  • no notifications: whether this owner should receive notification emails when messages need to be moderated.
  • concealed from list menu: list owners name or email normally appears under Owners at the top left of the List Home page.
  • private information: a brief comment which is only visible to the owners and moderators of the list. This might (for example) explain why someone has been added as a list moderator.

Sender lists (blocked senders, moderated senders and allowed Senders)

A drop down menu containing three separate pages which allow the list owners to define who is allowed to post messages to the list, in combination with the Who can send messages setting.

  • Blocked senders cannot post to the list: messages are silently discarded without notifying the list moderators. Useful for repeat spammers.
  • Moderated senders cannot post directly to the list: messages are redirected to the list moderators for approval. The sender will be informed that their message is queued for moderation.
  • Allowed senders can post to the list without requiring approval.

The three settings are checked on that order. A single "*" character can be used as a wildcard, for example: * Multiple wildcard characters are not allowed.

Manage archives

This page allows you to delete archives for entire months (list owners can also remove individual messages when viewing the list archives directly).

You can also download the messages from a specific month as a ZIP archive before deletion. The archives contain EML format mail messages, with one file per message. The filenames in the archive are numbers which count the messages in order of arrival in the archives.


This page lists the bouncing subscribers on your list, including the bounce score. Example:

Table to display list bounces
  Email Bounce score Details
Number of bounces First bounce Last bounce no score 1 29 Jan 2021 29 Jan 2021
Individual subscribers can be removed using the check box to the left of the email address. You can also reset the bounce score of individual subscribers when the bouncers are know to be a temporary issue. 


Allows list owners to search the log entries for their list matching a number of different categories (defaulting to all Categories):

  • Authentication  (logins)                                             
  • Bounce management                             
  • List Management             
  • Message
  • User preferences
  • User management
  • Web documents management (not  used on