I've had this issue for a while now - but the inconvenience it's been causing me makes me want to finally fix it.
In short, most links clicked on Steam or Steampowered.com do not work. Things such as links to the forums, Download Demo links, metacritic links all have no response when clicked through the Steam software.
When I go on Steampowered.com, and try to use install links and am asked whether I have steam installed - responding yes results in a error message which claims that Steam is not an associated protocol.
I have found an article relating to this in the FAQ. https://support.steampowered.com/kb_...2087-MZES-9065
I have done everything this article suggested. I tried different browsers, ran the Steam installation again (resulted in an error), reinstalled Steam from scratch, cleared and repaired the registry, added the registry entry by hand.
The error persists. I'm completely out of ideas, short of reinstalling the entire operating system. If anybody has encountered this issue and found any other workarounds, they would be much appreciated.
What is selected as your browser for opening steam links? Mine uses IE for no reason, but it does work.