You do not have to change the message format, but you can change it when there is a need. Microsoft Outlook provides 3 different formats: HTML, Plain Text and Rich Text.
By default, you have the HTML format which is also the best format to use when creating messages that look like traditional documents.
Part I: To change the format in a new or reply message:
Step 1: Click "New Email" in the Home tab, or "Reply" to reply an email;
Step 2: Select the message by using shortcut "Ctrl+A";
Step 3: In the message window, click the "Format Text" tab, and select one of the 3 format options: HTML, Plain Text or Rich Text;
Part II: To set up the default format for all emails:
Step 1: Click "File" from the Ribbon;
Step 2: Click "Options" from the left;
Step 3: Click "Mail" from the left navigation bar, and in the "Compose message" section, select: HTML (or Plain Text or Rich Text) as the default;
Step 4: You can also move down and click "Stationery and Fonts" to set up the font format for signature, new mail messages, replying or forwarding messages;
Step 5: Click "Font" to setup the font format in each scenario and click "OK" at the bottom;
