Reinstalled Steam And Now Can't Download HL2

[Toolsound]

Well, I kept getting the memory read error when trying to play HL2, so I reinstalled steam and now it doesn't give me the option to redownload HL2--it's like I have to repurchase it?

Also, I tried to register my old Half Life CD key and it says it's already in use now...WTF?!

Can I fix this myself or do I need to email steam?

 

[killer916]

Not to make you feel dumb or anything but are you on the same account you purchased HL2? Also you can only use a single cd-key once.