Click the software download link at the top of this page.
Select the correct machine type.
Add software to cart and checkout.
Click the download link after checking out and save the download somewhere on your computer (Downloads folder, Desktop, ect..)
After download is complete open the downloaded zip file and open the exe file.
Follow the installer instructions. Choose the correct machine type at the beginning of the installation and enter your serial number.
(if you do not know your serial number then use a number 1-1999 for 3D Xtreme non-S and S v1, or 2000+ for 3DXtreme S, or any number for 3D Pro, X, and XL or Elite)
After installer is finished there will be several new icons on your windows pc desktop, one for the Touch version, one for the Desktop version, one for the Device Manager, and one for the instruction manual.
Open the Touch or Desktop version and see if it connects to the key machine, if it does then you are done. If it does not connect then follow the driver installation and configuration instructions in you machine instruction manual.