Detect if a custom protocol handler is installed on client

We have a program that registers a custom protocol handler to allow automating some tasks. To see it in action, you can download our program from here: [login to view URL] Then navigate to this page: [login to view URL] and you can click on the images (which link to various crosus:// url's) to trigger CrosuS to do things. Clicking on the first item causes CrosuS to start downloading a game, clicking on the second item will launch the game, and clicking on the third item will launch the game and join a server. However, if the user has not installed the program, then clicking on the links won't work. We would like a way to detect if the user has not installed the program and redirect them to the download page. Otherwise, the link would work as normal. ## Deliverables Method for detecting if protocol handler is installed. Demo script and/or webpage that shows how to redirect the user to another page if the protocol handler is not registered. ## Platform Windows 2K/XP/Vista using IE6/IE7/Firefox