I added a Windows-only game to Steam using the "Add a game" > "Activate a product on Steam" option. After successfully adding it to the library, it tried to install it, resulting in an error message.
Verified this. When you redeem a Steam key, the installation wizard opens without checking if the product is supported.
Verified myself a few days ago.
dupe of #16
Nothing extracted yet.
I added a Windows-only game to Steam using the "Add a game" > "Activate a product on Steam" option. After successfully adding it to the library, it tried to install it, resulting in an error message.