If you are using a PoliteMail template and images are not scaling while the text and table are, you can use the mo_re100% fix that allows the images to scale with text and table.
Right click the image and click Edit Alt Text (format picture in older versions of Outlook). Add mo_re100% without quotes to the alt text of the image.
This instructs PoliteMail to change the image height to “auto” and the width to “100%” during sending (something you can’t do in Outlook). The effect is that the images will scale with the table they are inserted in.