Hi Ma_asseproj,
Thank you for posting, and I'm sorry to hear about your issue with activating Deskscapes 11. As basj has mentioned, typically this method linked here should resolve this issue.
If you've followed those steps exactly, and you're stilling unable to activate and use your software, it might be necessary to do a full uninstallation/purge of the software. In doing this, it is important to follow the steps exactly. You must reboot each time when you are prompted. It is also important to make sure you reinstall from a fresh download of the software from your Stardock account, to make sure you are using the latest version of the software download available to you.
Please let us know if you have any questions. If the above methods don't work, please describe where the activation is failing. If possible, a screenshot image of any error messages received, or any trouble areas is also always helpful for further troubleshooting.
Thank you and best regards,
Adam McGuinness
Stardock Customer Support Specialist