Keep in mind that when you add attachments to a mail message, it is easy to construct very large messages without realizing it.
To add a new mail attachment using the Add Attachment popup window, follow these steps:
Choose Add from the File menu at the top of the Attachments pane.
The Add Attachment popup window is displayed.
Select the directory name of the file to be attached.
Alternatively, you can type the path in the Go To text field.
Click SELECT on the Add button, as shown in Figure 4-21.
The file is added to the mail message attachment pane, as shown in Figure 4-22.