When creating an invoice and an invalid email address is entered in the 'Email' field an error message 'Invalid Email' will appear to the user and they will not be able to proceed until a valid email address is entered.
This error message means that the user cannot select a date in the 'Due Date' field that is before the date of the 'Invoice Date'.
This error message means that the user has inputted spaces; before, after or inbetween the characters in the 'Customer Invoice Number' field.
If the user runs this report with the 'From Date' earlier than 01/01/2005 then the error message "Invalid From Date. Date should not be earlier than 01/01/2005" will appear.
If the Subject and Message fields are not populated and the 'Send' button is pressed, then the above error message appears.