Mail filters

Server-side mail filters

If you receive mail from a variety of mailing lists or organisations you may find that you spend a lot of time sorting this mail into folders within your inbox. You may have even gone as far as creating mail filters in your email client to automatically sort your incoming email for you. This approach normally works well until you start accessing your email from lots of different mail clients in different locations. For instance at home you may use Mail, in work you might use Thunderbird, at a friends you might use the webmail interface and finally you may also want to check your email from your smartphone. Setting up the same filter rules across all these devices can be tedious if it is even possible. To get around this problem you can set up rules on the mail server so that your emails get filtered into the correct folders as soon as they arrive. You can setup and configure mail filters from the mailbox manager. Of course to do this you need to login to the mailbox manager web service. You can access the mailbox manager web interface at or securely at

Note if you login securely you will get a warning that “the identity of this website has not been verified,” or “server’s certificate does not match the URL,” or “server’s certificate is not trusted,” in your web browser. This is because the mailbox configuration service is hosted by our ISP, Dreamhost, and the certificate is issued by them rather than us. Your browser will normally let you view the certificate. If you click on this your browser will give you the option to always trust this certificate or install this certificate. Either of these should resolve this problem for you.

Once you login you will see a screen similar to that shown below. You can configure quite a lot of things from the mailbox manager interface. Many of these features are pretty self-explanatory but more details can be found in this post.

Mailbox manager screen shot

Under the heading Email Filters there is the option Add New Filter for [your email address]. Clicking on this link brings up a new window with all the available options to configure your filter as shown below.

Email filter options

Much like mail filters in your email client there is a line which defines the search criteria and then several lines allowing you to specify what you would like to do with email that matches the search.

The first line defines the search and the first drop down menu allows you to select the field you want to search in, for instance: the From field which would normally contain the email address of the sender; the Subject field, which would be the subject of the email; the To field, the email address or address that the email is being sent to; the Body, i.e. the main text of the email etc. The second drop down menu lets you specify whether you want the field to contain or not contain the search term. Finally the text entry field lets you define what you want to search for. In the example above it is the term amazon.

If you want to create more complex multi-layered searches you can add another search line by clicking on the ‘+’ icon to the right of the text field. Perhaps you might want to search for emails From amazon with the Subject bill. You can add any number of layers.

The next line defines whether you want the search to act when it matches any of your search fields or all of them. You can select which you want by ticking the applicable radio button beside all and any of the above. For instance you might want to use any of the above to match emails From amazon or From hmv.

The following five lines give you the options on what you want to do with your emails that you have matched via your search. In the example above the radio button Move it to folder: is selected and the text field specifies the folder Amazon. Note that the folder must already exist in your inbox in order for the filter to be able to move the email into it. All of the options are pretty self explanatory. Forward it to email address: will forward the email to another email address you specify, perhaps a work address or a friends address. Add your text to the subject adds some text to the subject line, perhaps you might want to add Urgent or something similar. Add the header your text adds a new header to the email which another email client may use to filter. Finally Delete it quite obviously deletes the email.

Finally under If this filter matches there is a drop down menu offering you the option to  execute and continue or execute and stop. The former will run this filter and then continue to run any filters after it in your list. The later will run this filter and then stop. It will therefore not execute any filters in your list after it. Generally your last filter in your list should execute and stop while all the others should execute and continue.

Once you are happy with your filter click on the Add Filter button and you are done. You’ll now be returned to the homepage of the mailbox manager and under Email Filters you will see your new filter listed. From here you can choose to Edit it or Delete it or you can add another filter. You can have as many filters as you want.

Filter added screen shoot

Some tips

It is worth testing your filters before you let them loose. If your filters aren’t working as expected make sure the search criteria matches what is in the emails your trying to filter exactly. Sometimes the easiest thing to do is cut and paste the From or Subject from your email into the filter. If your filter is catching additionally emails then try adding more terms to the filter with the ‘+’ button to improve the selectivity.