Since Nikon deactivated the old activation servers, you might need to use the "Offline Activation" method. Find the original installer (version 2.23.0 or earlier). During installation, choose "Phone Activation" or "Offline." If that fails, use the software in trial mode or explore the free alternatives listed above. It is often not worth the hours of frustration.
The software was sold in physical boxes with a CD-ROM and a —a unique alphanumeric string printed on a sticker inside the jewel case. This key was required during installation to unlock the full version, without which the software reverted to a 30-day trial. Nikon Camera Control Pro 2 Product Key
Nikon offers a 30-day free trial of Camera Control Pro 2. No product key required during the trial – just download from Nikon’s site and use it fully functional for 30 days. This is the best way to decide if it fits your workflow. Since Nikon deactivated the old activation servers, you