It is useful for the sender to know what you are replying about hence why it is default to include the conversation. The following will deselect that option. It is set up for each mail account separately. * Right click on mail account name in Folder pane and select 'Settings' * Select 'Composition & Addressing' * uncheck checkbox 'Automatically quote the original message when replying' * Click on OK You can always highlight part of the email content and then click on Reply. It will only include the section you highlight. That works whether you have set up to auto include or not.