To uninstall TouchMail, search in the Start menu for "TouchMail" then right click (or tap and hold) the program icon, then tap Uninstall. This will remove TouchMail from the device without affecting your email stored on your provider.

If you do not see an Uninstall option, then open the Start menu and type "Apps & Features" and select the resulting option, then find TouchMail in the full list of apps that is displayed.