Internet Explorer Can Affect Firefox
One would think that web browsers run independently of each other, that Google Chrome and Firefox, or Firefox and Internet Explorer would not affect each other.
Michael Horowitz over on Computerworld just found out that Internet Explorer can affect Firefox on Windows XP.
He changed the security level of Internet Explorer to high recently to improve the security level of the browser and harden it, and noticed from then on that Firefox would not download executable files anymore.
He linked it first to the recent service pack download and installation for Windows XP but found out later that it was actually a consequence of setting Internet Explorer's Internet Zone setting to high.
Firefox would not save executable files with the *.exe extension to folders on the operating system. The files would be created normally but with 0 Kilobyte. Firefox itself would cancel the downloads in the download manager right after they had been added to it.
Michael then tried to download executables with Chrome which worked out fine. He then knew that the issue was related to Firefox and discovered ways to resolve the issue directly in Firefox, at least for pre- and post Firefox 3.6 versions.
In Firefox 3.5 and 3.7 you need to enter "about:config" (no quotes) in the address bar and click through the warning about voiding the warranty.
- In Firefox 3.5.x the new option is called browser.download.manager.skipWinSecurityPolicyChecks and it should be set to True.
- In Firefox 3.7.x and newer, the new option is called browser.download.manager.scanWhenDone and it should be set to False.
Starting with Firefox 3, the Windows security settings for downloading applications and other potentially unsafe files from the Internet are honored on files downloaded by the Download Manager.
This allows, for instance, system administrators to block executable files from being downloaded by Firefox. This preference allows Firefox to ignore those OS-wide security checks.
Starting with Firefox 3.6, this preference is no longer used. (source)
In Firefox 3, if a Windows user has an antivirus program installed, it is launched to scan files when they finish downloading. During testing of the feature, concerns about delays and double-scanning files surfaced. As a result, this preferenceâ€”controlling whether the virus scan is automatically triggeredâ€”was created.
Starting in Firefox 3.7 (3.7a3pre nightly builds since 2010-03-06) this preference also controls whether or not the Windows security policy checks are applied for downloading and launching executable files. (source)
The new policy means that it is possible to resolve the issue in all versions of Firefox except the 3.6x branch. Firefox 3.6 users running Windows XP are affected by this if the Internet Zone of Internet Explorer is set to high.
Their options are to download executable files with another web browser, switch to a different version of Firefox or customize the settings in Internet Explorer so that executable files can be downloaded.Advertisement