Connecting POP And IMAP Clients To MS Exchange Server
The traditional method of connecting an email user to their MS Exchange Server mailbox is to use MS Outlook. However, as more and more mobile users wish to access their mailboxes remotely, Exchange Administrators are often required to configure the connections of a wider variety of email clients, on a mixture of platforms.
Compared to most email clients, MS Outlook's basic connectivity options are fairly easy to configure; you simply supply the computer name of the Exchange server and the name of the mailbox that you wish to access. But it is important to remember that Outlook is a proprietary client, and when you come to configure different email software, the configuration options are quite different.
Fortunately, even though you will have to supply different configuration responses to the ones you are accustomed to, you will find that they are the same from one program to another, although, naturally, you will find them in different places.
The basic configuration options are:
- The account type (POP3 or IMAP4)
- The address of the server handling incoming messages
- The address of the server handling outgoing messages
- The User Name for the email account
- The password for the email account
- The Internet email address of the email account
Whether or not you use IMAP or POP depends on whether or not you want to be able to use all of your Outlook folders. With POP, you can only access your Inbox, whereas IMAP allows you to access all of your folders, although things like Appointments still get treated as if they were messages, which isn't particularly useful.
The server addresses (POP, IMAP, SMTP) will need to be configured with the IP address of your Exchange server. You need to remember that POP is a protocol for receiving messages only, while SMTP is the protocol used for sending them. For some organizations the POP and SMTP servers are not the same machine, and this is why they are configured separately. In the case of MS Exchange they will usually be the same machine, which you specify in both fields. It is best to avoid putting a computer name here unless you are sure that the client will always be able to resolve it to an IP address, using an LMHOSTS file, for example.
When connecting a non-Outlook client to an Exchange mailbox the username has to be specified as
The email address that you supply will be the Internet email address associated with the mailbox.
As an example of a typical configuration, here are some screen shots showing the setup options of a handheld email client. Please note that the IP addresses, usernames and email addresses shown here are examples only, and you will, of course, need to supply your own values in order to complete a successful client configuration. Also note that the passwords here are saved with the configuration, whether or not you wish to do so is a matter for you own conscience.
Figures 1 and 2 show the configuration of a POP3 account, while figures 3 and 4 show the configuration of an IMAP4 account. You will note that the IMAP4 account lists all the Outlook folders, while the POP3 account has only the Inbox, Sent Items and some local folders.
Fig. 1 - Basic configuration of a POP3 account.
Fig. 2 - The Inbox of a POP3 account.
Fig. 3 - Basic configuration of an IMAP4 account.
Fig. 4 - The folders of an IMAP4 account.
In addition to the basic options already mentioned you will no doubt find others available to you when you configure the client. By far the most important is whether or not you want the client to leave the messages on the server when they are downloaded to the client. The failure to configure this option correctly has been the cause of much grief throughout the history of Internet messaging. If you don't want to come back to the office to find all your messages have disappeared from the server, make sure you find this option and configure it accordingly.
Older POP3 clients did not have this option and have generally been considered much less convenient than the IMAP4 alternative. Fortunately, modern POP3 software does allow retention of messages (often by default) and, because of POP3's simplicity, is regaining some popularity with those who just want simple Inbox functionality.