To leave messages on the server, you will:
When Outlook Express opens, click Tools, then Accounts from the menu bar.
Highlight the e-mail account you wish to change and click Properties.
Click the Advanced tab, then check the Leave a copy of messages on server checkbox.
To make sure copies of every message don't stay on the server forever (which can slow down your mail connections and use up your disk space allowance), we also recommend checking the box marked "Remove from server after X days". Choose a number of days that's long enough that you'll be able to read the messages in your other mail program (or Webmail).
Alternately, if you want to have our servers keep a copy of every message that you keep (don't delete) in Outlook Express � that is, to act as a backup system for the mail on your computer � you could check the "Remove from server when deleted from 'Deleted Items'" box instead of the "Remove from server after X days" box.
Click OK to close the Properties window, then click Close to close the Internet Accounts window.