Samuel Tardieu @

White List Email (WLE)

Do not ever receive spam anymore

I don’t know about you, but as far as I am concerned, every day, my electronic mailbox gets full of advertisements and other unsollicited commercial emails (called spams). Most spammers seem convinced that I am interested in a new passport from a non-existent country, in new pills against impotence, in working home and easily making a lot of money, in transfering money from Nigeria, in nude girls showing their “charms”, and so on.

In an effort to reduce the ratio of such messages in my mailbox, I use a combination of several systems:

  1. SpamAssassin attempts to detect common patterns used by spammers in incoming messages.

  2. A home-made confirmation system called WLE (for White List Email) asks to the senders of messages which went through SpamAssassin to confirm that their email is legit.

This second step is necessary and useful: spammers use more and more elaborated stealth techniques to avoid being caught. Moreover, most of the time they use invalid sender addresses so that they do not get overthrown by all the errors (their files are not always up-to-date and include addresses that do not exist anymore). As they do not receive the confirmation message, they cannot answer it and their unsollicited email does not end up in my mailbox.

Of course, once someone confirms that her email is legitimate to my filtering system, her email address is automatically added to an authorized address list: all her new messages will go through the system without any new confirmation being needed. Also, when I send an email to someone, her address is added to the list of authorized addresses and no confirmation request will be sent to her when she writes back.

If you were sent to this page by my confirmation system, thanks for taking the time to answer the request. It will take you only one second and allows me to answer my messages much more efficiently. Everyone (except the spammers) benefit from that.


I got asked several times what are the differences between WLE and TMDA. Here is a partial list of the advantages of WLE (without any particular order) that I thought of while editing this page (there are others):

  • When someone in your authorization list sends you a mail, all the recipients may be (at your option) added in your white list. If a friend of yours send an email to a list of people she knows, those persons can answer back to everybody (you included) without needing to confirm their message (maybe they haven’t ever heard anything about you, they would be surprised to get a confirmation request coming from you).

  • If a mail contains a special string (in the headers or in the body), it gets automatically accepted and the sender and all the recipients are added to my white list. This is based on bad practice: people often quote a whole message when they answer, including the signature (which contains the magic string); they don’t need to confirm their message when they answer me, even if they answer privately to a message posted on a mailing-list or a Usenet newsgroup.

  • WLE includes a vacation system which sends (cleverly) messages when you are away for an extended period of time.

  • WLE automatically removes ongoing requests if the confirmation mail returns with an error. Most unsollicited commercial messages are removed automatically from the waiting queue.

  • WLE can be controlled by mail: you can consult and manipulate ongoing requests with your favourite email client.

  • I don’t like the idea of automatically using several email addresses, as TMDA does. WLE lets you use your real email address, while requiring only a very small number of confirmations.

Thanks to John Peters for his proofreading.

Getting WLE

You can either download a packaged version, or get the latest development version of WLE.

Packaged version 0.4

You can download WLE 0.4 for Unix, distributed under the GPL.

Development version

You can get the current development version of WLE using git:
git clone
This will create a wle directory in which you will be able to record your own changes. You can also browse the WLE repository on GitHub.

Contributing to WLE

Reporting bugs and asking for features

If you find a bug or have an idea for a new feature, you might consider adding a new issue. The more precise you will be in your description, the more useful it will be.

Submitting patches

Patches are gladly accepted from their original author. Along with any patches, please state that the patch is your original work and that you license the work to the WLE project under a license compatible with the current one (GPL).

To propose a patch, you may fork the WLE repository on GitHub, and issue a pull request. You may also send patches and pull requests by email.