Buy it from the DART web site. (That would be here from this page.)
A CD will be sent to you and should arrive in a few days.
Un-install the DART trial version using the Windows un-install utility.
Install instructions are on the CD. Just load it in the CD reader and make it ready.
Follow the install links.
For installation of older DART programs on Windows 7 make sure to set DART program file properties Compatibility to checked and Windows XP (Service Pack 3) after the install using Windows Explorer. Do this -
Select My Computer, then C Drive, then Program Files (x86), then DART program file.
Then hi-light the DART program executable file and right click on it
System Notes: DART XP Pro runs on Windows 10®, Windows 8®, Windows 7®, and Windows XP® with DART application file compatibility properties set to Windows XP.
Our software registration system requires both a valid email address and ZIP (Mail) code. We retrieve and use the ZIP code from the billing/shipping address. Make sure you provide your address as part of the buy information
* If purchasing with a check, your software order will not be shipped to you until the check clears (typically 3 to 5 business days).