is free, open-source software, you might have noticed a recurring "donation prompt" appearing when you close or update the app
Once you receive your registration key via email (usually a .cyberducklicense file), installing it is simple: Double-click the license file you received in your email. Cyberduck Registration Key
The Cyberduck case illustrates that donation reminders may have limited effectiveness, but removing them does not eliminate user demand for perceived "activation." Better education about open-source licensing and free software could reduce exposure to fake key scams. is free, open-source software, you might have noticed