I have the feeling that if his computer is so old that it doesn't even have a DVD drive then its probably too old to run portal.
Lol he probably tried to put it in the floppy disk drive.
i downloaded portal but all it says is "you need pixl shader 1.1 to run this program!' can you give me a link to that oh and i have the best grapics card my computer can handel
portal 2
Did you buy it off of Steam?
My computer was before DVD drives and it can run portal.
Keep dreaming.