All email clients supported by CIT (and most email clients in general) have a feature called rules (sometimes called filters). Rules allow you to define certain conditions under which certain actions are taken. For example, you could create a rule so that all email messages coming from your boss get marked as high priority. Or one that selects all email with “in your area” in the subject line to get deleted.

The situation gets complicated because many people check their email from a variety of devices or locations. If the rules you've set up vary from device to device, the behavior of your email will also vary.

Fortunately, most rules set up through an Exchange client—Outlook for Windows, Outlook for Mac, or Outlook on the web—are “server-side” rules, meaning they are processed on the email server, not on the device you’re using at the moment. Any server-side rule, no matter where you created it, will be applied consistently, no matter where or how you check your email.

The other kind of rule—client-side—is where the problem comes in. These rules are specific to the email program installed on a particular computer or device. This means that the actions taken automatically by your rules will be different on different devices and you may not see the behavior you expect to see.

For simplicity’s sake, we recommend that you create your rules using Outlook on the Web, because it can only work with server-side rules, so there’s no risk of setting up a client-side rule.

Most rules that are set up in Outlook apps are server-side, but if you choose a client-side type of rule, Outlook will notify you.