The notification.properties file (in Install Home/lib/msgs) contains properties that specify the template file to use for each notification type. For example, here are the lines from notification.properties that specify the template files to be used for item notifications:
itemEmailFileHTML.string=item_email.html itemEmailFileText.string=item_email.txt
The setting of the -Ddisable_htmlemail property chooses between the HTML and text versions of the template. If -Ddisable_htmlemail is set to false, the Event Service uses item_email.html when it sends an item notification. For information on setting this property, see the Oracle Enterprise Performance Management Workspace Administrator’s Guide.