help please l4d problem

[LA_MERC_Sniper]

i bought the cd tonight and am trying to download but it stops will not finish downloading

[coors]

Well how much room is left on the HD? Might also consider Defraging.

[LA_MERC_YellowDog]

have you rebooted, opened steam, and tried to run the App.. somtimes this will kick start the D/L'ed again in steam.