I have tried to change it manually, but I can't find the Layout tab so I can set the left margin. You would think each theme provided would adjust the margins automatically for its theme graphic. The problem is when I compose a new email, the left margins are not offset by this, and stay at 0, which puts my text in the graphic. This theme places a spiral notebook graphic down the left side of the email body overlapping the body by about 1/2' wide. I have 'Use theme's font' selected for the theme font. I'm using the theme Notebook under Mail > Stationery and Fonts in Outlook 2016. If you change the values, click the Set as Default button at the bottom of the dialog, then choose All documents based on NormalEmail.dotm template and click OK to commit the changes. Adjust the width of the compose message form instead. Do not use indentation or margins to make line wrap on wide screen monitors while you are composing them this will affect the margins and format on the message the recipient receives. If you want to use indentation, keep it very small. The Left and Right Indentations should be set to zero.

(If the ruler is visible, you can point to the indentation triangles and double click to open the dialog instead.) On the Format tab, click the Expander icon to open the Paragraph dialog. Both the Left and Right Indentation should be set to 0 (zero). To check or adjust the margins in Outlook 2010 and up, you need to look at the Paragraph settings and Page Setup. It's better to adjust the width of the compose window if you need to make the lines shorter and easier to read while composing messages. Trying to force line lengths using margins or the Enter key to break lines only results in readability problems for the recipient.

Outlook doesn't have an option to set the width of a message - it uses the full width of the message window and wraps text in the window as needed. If the recipient opens the message in a window 500 pts wide, the message would be indented 200 pts from the right edge. As set in this screenshot, the right margin is approximately 200 pts.

Recommended setting: keep the right margin triangle at or very near the right edge of the page (identified by red arrow).

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