The issue for programmatically setting FireFox as the default browser came from our Citrix environment. We were using Internet Explorer 8 and did not have the ability to update to IE 9 to satisfy some specific browsing compatibility needs. Being able to do this programmatically is a must, and the manual ‘registry’ options just didn’t seem appropriate considering the number of changes that needed to be made.
Basic searching led to the following command:
firefox.exe -silent -setDefaultBrowser
This command option, however, appears to have been removed at some point and no longer works.
Finally I found this command:
"%ProgramFiles%\Mozilla Firefox\uninstall\helper.exe" /SetAsDefaultAppUser
So far, this appears to have done the trick!
