This article describes alternate ways of setting Firefox as the default browser when setting it from the Firefox optionspreferences window does not work.
Symptoms of this problem can include:
The preferred method of setting Firefox as your default browser is described in the Make Firefox your default browser article. Most external programs will open links in Firefox if it is set to be the default browser using that method.
Follow the instructions below if you have tried the steps in the Make Firefox your default browser article and found that they did not work.
Some programs are hard-coded to open Internet Explorer rather than the default browser. Programs that do this are listed below along with possible solutions, if available.