This guide is for MS Outlook Express 6, although it will probably be fine for most other versions of Outlook Express.
The guide assumes you have access to your e-mail account's pop3 information and are connected to the Internet.

		Firstly, run Outlook Express as usual, then go to the “Tools” drop down box and select and click “Accounts…”.
		Once at the “Internet Accounts” box, click “add” and then select and click “Mail…” which will start the “Internet Connection Wizard” which allows you to set-up a pop3 e-mail account.
		The first part of the wizard asks you to enter a “Display name” which is the name that will be associated with your new pop3 account and that will display for a recipient of an e-mail you send to see. This name can be changed later if you want. When you have entered an appropriate name (your own name for example) click “Next”.
		The next section of the Wizard requires the e-mail address you are setting a pop3 account up for. When you have entered the address in full, click “Next”.
		The next part of the Wizard requires you to enter the e-mail server information for the pop3 e-mail you are setting an account up for. You need to go the e-mail provider’s (Yahoo! for example) web site and follow their instructions online to obtain this information. It is usually easy to obtain and if you cannot find it, you can usually get it by e-mailing your e-mail provider’s technical support. Once you have entered the pop3 server information, click “Next”.
		Sometimes you may find that the pop3 information you have entered for your e-mail account doesn’t allow you to send outgoing e-mail. This can sometimes happen and is usually resolved by entering the outgoing mail sever information that is used by your Internet Service Provider (ISP). Always try your e-mail provider’s pop3 server information first, but if problems occur with outgoing mail, try your ISP’s outgoing mail sever information.
		Once you have the appropriate pop3 e-mail server information entered, the next section of the Wizard asks for your e-mail account’s “Account name” and “Password”. Quite often with pop3 e-mail, the account name will either be the first section of your e-mail address (the bit before the “@”) or it can be the whole email address. It is usually the same as whatever you use in conjunction with your password to access you e-mail online. In most circumstances, “Secure Password Authentication” is not required for Outlook Express to access your e-mail, so you will most likely need to leave the check box empty. Otherwise, select the check box. When all the relevant information is entered, click “Next”.
		You will now be shown the “Congratulations” section of the Wizard where there is no more information to enter. Click “Finish” to end the set-up Wizard.
		You will now be back at the “Internet Accounts” box and should be able to see your new e-mail account in the list of accounts. Click “Close” to close this box and go back to the main Outlook Express interface.
		Once back at the main Outlook Express interface, click the “Send/Recv” button to make Outlook Express check your newly configured e-mail account for e-mail and download the e-mails on your e-mail provider’s sever. If this process completes without any error messages, you have now successfully set up a pop3 email account in Outlook Express.
		Sometimes during the send and receive process, you may see a "Logon" message appear. This can appear for several reasons. One reason is that your e-mail account was set-up online too recently and hasn’t been configured yet on the e-mail provider’s servers. If this is the case, you simply have to wait until it is fully active, which could take up to 24 hours depending on your e-mail provider. Another reason could be that you have mistyped your password, sever information or some other information when setting the account up. If you think you have entered incorrect information, you will need to close the log-in message by clicking "Cancel" and go back to the "Internet Accounts" section, by going "Tools" and "Accounts..." again.
		Once back at the "Internet Accounts" section, select your newly set-up e-mail account and then click "Properties".
		Once at the properties section you will have access to all the information you entered in the initial set-up process and will be able to change it if it is incorrect, or needs to be amended for some other reason. Once you have made any necessary amendments, click “Apply” and then “OK” and then check again using “Send/Recv” to see that your amendments were successful.
		Should you want to remove an account from Outlook Express, you need to go back to the “Internet Accounts” section you visited earlier, select the account you want to remove and then click “Remove”. If you are prompted to confirm your decision to remove an account, click “Yes”.

If you want to add additional e-mail accounts, all you need to do is repeat the process again and you'll be able to.