Once you have a license for O&O Defrag 18 Pro, download the test version. You’ll then be able to enter your license code to convert your test version into a full one.
You will not be able to use the registration information from a previous version (O&O Defrag 17 and below) to unlock a current one.
The O&O Defrag 18 Professional Edition may only be used on desktop or notebook systems. Servers require the O&O Defrag Server Edition