Why does the Software Activator say
Activation failed. Please try again ...
when I install my activation code?
This message may indicate that the activation code that you entered contains a typo. The best way to enter the activation code is by copying the code (Ctrl-C) from the activation e-mail and pasting it (Ctrl-V) into the Software Activator. There is also an option to activate online. In this case you do not have to enter an activation code.
Also see: Best Practices when activating Deep-Sky Planner 9