Steam – How to see what all DLC I have in Max Payne 3

max-payne-3rockstar-games-social-clubsteam

Recently there was a deal in steam for Max Payne 3 and All its DLC. I purchased the game along with the DLC. Now whenever I try to redeem the code for DLC it always says

Redemption code already in use

Now that could mean:
a. There is some issue with all the redemption code I got from steam.
b. By default steam have activated all DLC for me and I don't have to redeem any code.

If it is b then how to see/confirm if I really have all DLC or not. ( and if it is a then what to do? )

Edit @keavon
Here is what I see in steam Max Payne 3 properties:
enter image description here

This says installed. That means all DLC already installed?

Best Answer

If you already own the DLC, it will give you the error Product Already Owned. You would also get that message if you try activating a used key for a product you already own. This means that the key has been used, and you do not own the product. You are getting that error because the key has already been activated.

To answer your question about checking the DLC you own, right click the game in your library, click Properties, and check the list in the DLC tab.