Finding a CD key for a legacy version like Counter-Strike 1.4 generally involves using keys associated with the original
If you are looking to play Counter-Strike on modern hardware, the CD key system has largely been replaced: Steam Version : You can purchase Counter-Strike 1.6 directly on the Steam Store Counter Strike 1.4 Cd Key Pc
From Liquipedia Counter-Strike Wiki. [e][h]Release 1.4. Patch Information. Version: 1.4. Release Date: 2002-04-24. Highlights. Liquipedia Finding a CD key for a legacy version like Counter-Strike 1