So I bought a physical copy at Best Buy and I'm looking to activate it on steam but it keeps giving me the error: "Invalid Product Code." So I checked it several times, tried with dashes, without dashes and it isn't seeming to work. If I already activated the game in the actual game terminal can I still use it for steam as well? Anyone else experience this already?

If you didnt bought it on steam? how do you think it can work for steam?

Because there's an option to "Activate a product on steam," by entering the products key. I can add the launcher to steam no problem, I was just wondering how to activate it.

Add non steam games then? The lowest option! I did that works for me.

Only some games have the option to activate on steam. It really depends on if the developer for the game decided to do that or not. With crysis 2 I don't think that is the case.

I didn't buy it from steam either (it was on sale at Best Buy) so instead I just added the launcher to steam and play through that (so i get the overlay).

Why do you want to activate it?

Sounds kinda stupid but when I start up steam, my friends get notified that I'm playing a "non-steam game," whereas I want them to know that I'm playing Crysis 2, so that they log on as well to play with me or hop on mumble. I can live without it, but it's just nice.