Remembered that I had the CD for Half-Life and learned you can put the CD key in to unlock it. Was surprised that I also unlocked the add-ons with this version. :
![How to Find Steam Game Serial Key or CD Key? [2 Solutions]](https://www.easeus.com/images/en/screenshot/todo-pctrans/steam-cd-key.png "How to Find Steam Game Serial Key or CD Key? [2 Solutions]")
How to Find Steam Game Serial Key or CD Key? [2 Solutions]
How to activate cd keys on Steam. - AllKeyShop.com
Steam Community :: Guide :: How To: Guild Wars & Steam
Steam Community :: Guide :: Steam: How to activate CD Game Key.
where do i find the serial code from a steam download - Page 2 - Answer HQ
How to redeem Steam keys and codes on mobile and in app | Pocket Gamer
How to Activate Third Party Game Codes in Steam
Where to find CD Key requested on starting a game through Steam? – Fanatical.com Customer Services
Tutorial: How to activate a game cd-key on Steam - YouTube
How To Redeem Steam Keys – Humble Bundle
Activate Steam Key from Context Menu
I can't add my CD keys on Steam, because it says it's already registered. Yes... it was me like 1 year ago. What can I do? I want to come back continue
How To Redeem A Code On Steam - Unlock A Game - YouTube
How To Redeem Steam Keys – Humble Bundle
How to activate cd keys on Steam. - AllKeyShop.com
How to activate cd keys on Steam. - AllKeyShop.com
How to activate CD key on Steam? A simple tutorial on GG.deals
How to Use Steam Keys: 12 Steps (with Pictures) - wikiHow
How to Use Steam Keys: 12 Steps (with Pictures) - wikiHow
Steam now allows activation of game keys from web browser
![How to Find Steam Game Serial Key or CD Key? [2 Solutions]](https://www.easeus.com/images/en/screenshot/key-finder/article/products/find-software-product-key-2.png "How to Find Steam Game Serial Key or CD Key? [2 Solutions]")
How to Find Steam Game Serial Key or CD Key? [2 Solutions]
How to view CD key for a Steam game? - Arqade
