Keys from my key generator: 4801- 3469- 0573- 0155- 0625- 8957- 8646- 6940- 6. When searching for Half Life do not include words such as serial, number, key, license, code, torrent, etc. Excluding words such as these will result in much more accurate results. Recheck your spelling for Half Life just in case, you might also want to try searching without the version number.