When you click a link on Windows Vista, the page opens in Internet Explorer even if another browser is selected as the default.
Set the default browser in Program Access And Computer Details.
The registry entries for shell exec on Windows Vista are not correct even when a browser other than Internet Explorer (such as Firefox) is set as the default using Start > Default Programs > Set Your Default Programs.
To correct this issue, set the default browser using the following steps:
The shell exec registry settings are set properly and allow navigateToURL and hyperlinks within text controls to work as expected.
Windows Vista does not make the required additional registry entries correctly when a browser other than Internet Explorer is set as the default browser. When an attempt to load the URL is made, Adobe AIR uses Dynamic Data Exchange (DDE) to connect to an open instance of the browser registered for URL requests. If that fails, Adobe AIR falls back on Shell Execution.