We all know the problem: e-mail you don't need or never want is still sent to you, and it ends up on the place where it takes the most effort to ignore or remove it: your mobile inbox. This could make mobile e-mail even counterproductive.

It isn't just SPAM, it can be anything. It comes from friends and colleagues too. It can be the invitation to yet another party, people fighting over something using e-mail as a medium (and you in the CC), invitations to eat cake to celebrate something, a complaint about workplace tidyness or someone reporting that a car has its lights on in the parkinglot. It is completely nonsense, especially since you will probably be out of the office anyway. But it will still trigger an alarm you will respond to. It is noise in your daily routine. It makes you less effective and it should go.

To put an end to the nonsense, you could off course turn of the alarming, but that would perhaps make you anxious: you might miss e-mail. So filtering might be an option. Automatic filtering is definetly an option. Thigs you might consider:

There are some very obvious groups of e-mails that can easily be redirected from your inbox to something else (be it the trashcan, be it a special folder that you will read later when you are at a desktop):

• SPAM: most SPAM-filters bounce the obvious stuff, and mark the things they suspect being SPAM (with around 95% accuracy). By redirecting this potential SPAM to a special folder, you can look for that remaining 5% when you are working on a desktop, but you are not bothered by it on your mobile.
• Mass mailings: Newsletters, store-updates, mailinglists, blogcomments, forumthreads, and LiveJournal mails. Most of them are a waste of time, none of them are important or require immediate attention and there are an awful lot of them.
• Internal e-mail to every employee: None of them are time-pressing, most of them are the "there is a car in the parking lot with headlights still on" kind and no one is going to notice if you will not read them the same day. Just park them in a special folder and read them when you have reserved your time.
• Mail where you are not in the TO-field: If people just dump information upon you without clear task or goal, they do not deserve your immediate attention.
• Mail marked FYI or OT or having low priority: even if people take the time to specifically address you, marking e-mail with a low priority, with For Your Information (FYI) or Off Topic (OT) signals you can safely ignore it for the time being. Some senders/organizations are mature enough to introduce these annotations (as well as ACT, for action) allowing quick browsing and filtering.
• E-mail that is forwarded: research has indicated that forwarded e-mail is not considered as important by recipients anyway, so why not automate this.

Blacklisting the origins of real SPAM

A good habit to maintain is using the "Add sender to Blacked Senders List" when you do recieve SPAM. Most senders originate from obscure domains anyway. Blocking them resolves a lot of problems since domains are recycled by SPAMers and the list is automatically transferred to the Exchange server. So when filtering is active, you can blacklist domains in order to prevent SPAM flooding your mobile inbox.

Filtering using rules from the OWA-webinterface

The webinterface provides the most basic functionality, but that might be effective to kill off sme of the above causes of noise in your inbox. After you login, you can select the rules:

After clicking the rules, you get an overview of all the rules you have active on the server:

It might be that you have rules active already: the greyed rules are rules that are executed serverside but can only be editted by the outlook client. When you select a rule, you can move a rule up or down. This is not just formatting, this is an indication of precedence: the highest rule will be executed first.

If you click on "New Rule", you get the following dialog:

Here you can select on which criteria you want messages to move out of your inbox. Some examples are:

• The From field: more mature organizations use special aliases like "all" or "employees", that allow great filtering.  Just redirecting them to specific folders can save you a lot of unwanted, non-critical, e-mail on your mobile device;
• The Subject allow you for great filtering. Terms as "cake", "carlights" etc. could help you get rid of anoying e-mail when you are on the road. Some e-mail filters mark suspected SPAM with specific tags. By focussing on these tags you can kill SPAM on the serveride, ot just redirect it to a place you will look when you have time to do so;;
• The Importance might be an indicator as well. Perhaps you only want high priority e-mail on your mobile device: redirect all unimportant mail to another mailbox and it will not bother you any more.

Filtering using rules from the Outlook desktop client

It is also possible to create server side rules from the outlook desktop client. You can do this by selecting the "Rules and Alerts" from the "Tools":

 You get the followng dialog, allowing you to add and edit rules:

 By Selecting "New", you get a wizard that helps you build rules:

Like the webversion, you can select several options. In the desktop version there are a lot more options are available. Specifically:

• Allows you use a specific outlook adressbook as a filter, basically making it a whitelist to your device.
• Allows you to filter on specific words in the message header allowing you to use passive spamfilters, like SpamAssasin, to filter SPAM before it reaches the inbox on your device.
• You can select rules to which you can create exceptions. In fact one of the most powerfull extra options is the availability of exceptions. You can prevent, for example, that e-mail is moved to another folder when you are explicitly in the To-line or that comes from a highly trusted source.

After this you can name the rule and finish up.

After you have completed this, the rule will run on the server. So even when your client is not logged in, the e-mail is still moved away from your inbox, preventing downloading onto your mobile inbox.