Since Firefox 3.6 is no longer supported, it has been updated to Firefox 12 to help keep your computer and personal information safe. Some users are then told they need to update again. Although this seems odd and inconvenient, it's expected. This article explains why.

Why do I have to update Firefox twice?

If you were using Firefox 3.6, we have updated it to Firefox 12. This is not the latest version of Firefox. We would have liked to update Firefox 3.6 users to the latest version of Firefox but not everyone can run it. Firefox 12 can determine if your computer is able to run to the latest version of Firefox. If your computer is able to update, you are then shown a message about getting the latest version.

• If you see the message about updating to the latest Firefox, please follow the instructions to keep your computer and personal information safe. For details, see Update Firefox to the latest release.

People using Windows 2000, the original version of Windows XP and Windows XP Service Pack 1 can't update to the latest version of Firefox. To learn about update options, please see:

• Firefox no longer works with some versions of Windows XP
• Firefox no longer works with Windows 2000