As a Project Administrator you can set Response Required as a mandatory field for mail types.
Project managers running time-critical projects often need to ensure that the queries they send are responded to in a timely fashion. You can help them with this by making the Response required field mandatory. When they select one of the options from the drop down list it enforces a due date to be entered.
You can do this for all Mail Types except Transmittals. You can also set up default response times for mail, which automatically show how soon a response is expected.
Now when a new mail is created and the relevant Mail Type is selected, the Response required fields are marked with an asterisk to show they are mandatory: the mail cannot be sent without the fields being completed. In this example the Type of mail being sent is Action Item.