invalid CD key

[phillipstall]

I've owned the original CDs for Half-Life Platinum Collection for years, and I bought them new. I cannot install this game from the original CDs onto my new computer (Windows 8). So, I thought I would be able to play via Steam. When I type the CD key into Steam, I get an error message something like "....CD key invalid." Looks like someone else is using my CD key! Don't know what to do. Can't seem to contact Steam support.... Anyone else know how to get around this problem?

[PirateGary]

try to add the Key with and without dashes first. Contact the SW maker to question them. It may not be a Steam Sponsored Game. If Non-Steam go to Add NS Game then find it on the computer list.Will it install to the Computer, if not the list will not include the game.

[Silicon Vampire]

invalid means just that. you would be told if a duplicate key however, I am not sure those keys were ever accepted. I *think* they may have been distributed by an early publisher and never authorized on Steam. I could be way wrong.

[Froggy424]

Actually these codes worked for me - I own both of the original Half Life and Half Life 2 collectors edition.. I went through many of my old games that pre-dated steam and the ones I found available on here I put in -- a few didn't work but most of them did. Both half life games worked for me --

[cSg|mc-Hotsauce]

Originally posted by Froggy424:

Actually these codes worked for me - I own both of the original Half Life and Half Life 2 collectors edition.. I went through many of my old games that pre-dated steam and the ones I found available on here I put in -- a few didn't work but most of them did. Both half life games worked for me --

All Valve games activate on Steam. Some others will but most old games won't.