If you're still experiencing issues with activating Starsector using your activation code, don't hesitate to reach out to the developer's support team or the retailer's customer support for further assistance.
Q: Can I use a Starsector activation code on multiple computers? A: Yes, you can use the same activation code on multiple computers, but you'll need to activate the game on each computer separately.
There is only to buy a Starsector activation code: The Fractal Softworks Website.