If you read your emails on more than one computer you may want the emails to be left on the server so they don't disappear before the other computer has a chance to download them. It can also be a good idea to leave them on the server in case there is a problem with your computer. It is possible to do this when you create an email account in Microsoft Outlook, or you can go back and change this later on. Go to http://www.computeractive.co.uk/2248493 for the full text