After briefly trying Star Downloader and later uninstalling it, I found that Firefox would not download any exe or zip files. Instead, I would be greeted with a blank tab with the exe URL in the title bar. Everything else seemed ok.
To troubleshoot the issue I did as followed
1) Disabled all my fancy extensions to get as much of a pure firefox as possible.
2) Checked the file associations for application mime types and exe/zip associations opened in the current application. To access these options go to:
Tools->Options->Downloads->View & Edit Actions…
You will see the ‘Download Actions’ dialog. Look for anything that has Star Downloader / Opera plugin and change the Action to either save or use another program to open that kind of app.
3) On restarting firefox the problem was still there. In firefox, going to About:plugins in the address bar, showed me that the star downloader dll (npstar.dll) was still in firefoxs plugins directory. Even though the zip/exe associations were now cleared from the download actions dialog, they were still getting handled by the plugin.
4) Closed Firefox. Deleted npstar.dll from E:Program FilesMozilla Firefoxplugins. Restarted firefox.
The behaviour was now restored. I reactivated my extensions and enjoyed being able to download again.