I have a large client, that like many other large companies, has a policy which only allows IE6 (soon to upgrade to IE8). Recently, a requirement came in to auto-launch a thick client application from a link on an intranet site. Immediately, I began to refute this requirement due to security issues revolving around browser-to-desktop communication.
Since I was able to assume IE will be the only browser using this application, I started to “Google” my options. Surprisingly enough, I found this link: http://msdn.microsoft.com/en-us/library/aa767914%28VS.85%29.aspx.
This step-by-step identifies a way in which you can add a registry entry, which will allow you to register a specific application to a URL protocol. So, if you wanted to be able to launch firefox from IE while passing the command argument “google.com”, you would simple register “/path/to/firefox.exe” under the alias “firefox”, then you can create a link with an href of “firefox:google.com”. This will now launch firefox and redirect to Google.com.