IMAP (Internet Message Access Protocol) leaves the email messages on the server. Not like POP3 where it deletes the email from the server once it's downloaded. IMAP is good if you check your email in multiple computers, cellphones and tablets.

Open Outlook Express.
Click on Tools / Accounts...

In Internet Accounts, click on the Add button and then click on Mail...

Display name:

Type in your name.
The name you use will be the name that will appear on emails that you send, reply or forward.
Click the Next button.

E-mail address:

Type in your glisnet email address.
Click the Next button.

Type and select the following information.

My incoming mail server is a

IMAP

server.

Incoming mail (POP3, IMAP, or HTTP) server:

mail.mailconfig.net

Outgoing mail (SMTP) server:

mail.mailconfig.net
Click the Next button.

Type and select the following information.

Account name:

Type in your email address.

Password:

Type in the password for your email address.
Place a check next to Remember password
Click the Next button.

Click the Finish button.

You'll see the new account you just created.
Click the Close button.

You'll see the new account you just created.
Click the Close button.

Click the Yes button.

Click the OK button.

Once it's done downloading emails, you can start using Outlook Express.