Change the Default E-mail in Microsoft Outlook
You may want to change the default e-mail account through which, you wish to send all new mails. This section tells you how to change the default e-mail in Microsoft Outlook so that all the new mails are sent from the new account. If you want to know how to change the e-mail address on Outlook for sending a particular e-mail and do not wish to change the default e-mail account, skip to next section.
To change the default e-mail in Microsoft Outlook:
1. Open the Account Settings Window. In Outlook 2003, click on Tools menu and select E-mail Accounts. In the box that appears, select View or Change E-mail Accounts. In Outlook 2007, click on Office button and select Account Settings. Click on Account Settings in drop down box. In Outlook 2010, click on File tab and click on Info. Click Account Settings. A drop down box appears saying Account Settings. Click it.
2. In the Account Settings window, make sure you are on the e-mail tab. When you are on e-mail tab, Outlook displays a list of all the configured e-mail addresses. It automatically highlights the default account that is currently being used to send e-mail accounts. To change default e-mail in Microsoft Outlook, select the e-mail account that you wish to make default. After selecting the e-mail account, click on Set as Default.
3. When you click on Set as Default, you will notice that the e-mail account is moved to the top of the list and is preceded by a tick icon. This means that the account you selected is now the default e-mail account in Microsoft Outlook (The icon does not appear in Outlook 2003). Click on Close to close the Account Settings window.
This explains how to change default e-mail in Microsoft Outlook for all new e-mail messages that you will be composing. Read on to know how to change e-mail address on Outlook for a single e-mail without changing the default e-mail account.