Steam Accounts for HL2

[zorbathegeek]

I bought a 2nd-hand copy of HL2

Is it true that I won't be able to use it because of some sort of anti-piracy thing?

It's an original copy with a product key etc. - was it a waste of money then?

 

[Cole]

That matters:
-Did the person before you ever create an account on steam and tie his cd key to it?
-Did he give you the account name\pass if he did so?

You see when you buy HL2 you have to put the cd key in steam under an account. It can only be registered to one account.