Although the process for doing so requires a bit of a workaround, adding a watermark to the background of an outgoing Microsoft Outlook mail message may allow you to keep more control of your messages. Because Outlook doesn't have its own watermarking process, you must first create or obtain the watermark. When you've decided what to use -- anything from a single word to a company logo or a long disclaimer is permissible -- adding it to the outgoing message's background requires only a few clicks.
Open Microsoft Outlook. Click the "Mail" button on the bottom left of the screen.
Click the "New E-Mail" button. The "Untitled Message" window will appear.
Click the "Options" tab at the top of the window. Click the "Page Color" button. Click "Fill Effects."
Click the "Picture" tab. Click "Select Picture." Browse to the picture file to use as the watermark and double-click it.
Click the "OK" button to close the "Fill Effects" window, insert the watermark and return to the message window.
Type the body text for the email, which will appear over the top of the watermark. Fill in the "To" and "Subject" boxes and click "Send" to send the email.
Software programs that will help you create a watermark image include Paint (included with all Windows operating systems), Adobe Photoshop and Adobe InDesign. Options for the watermark include typing the words "Confidential" or "Security" or using a photo, image or logo.