If you encounter a "Problem validating your serial key" error, common solutions include: Richienb/synergy-serial - GitHub
The "core" engine of Synergy is actually open-source. If you are tech-savvy, you can compile the source code from GitHub for free. You lose the polished user interface and easy auto-configuration, but the functionality remains. symless synergy serial key
: Paste the serial key into the software for offline activation. Is There a Free Version? If you encounter a "Problem validating your serial