From MozillaZine Knowledge Base

Firefox may report that an update is available even though you are running the most recent version of Firefox and no updates exist. One of these methods should fix the problem.

Method 1 Close Firefox and delete "active-update.xml", "updates.xml", and the "updates" folder from one or both of these locations:

• The Firefox installation directory; for example, on Windows, C:\Program Files\Mozilla Firefox or C:\Program Files (x86)\Mozilla Firefox on 64-bit systems. [1]
• (Firefox 2.0.0.2 and later) The folder where Firefox stores temporary application data for your operating system. [2] [3]
  Important: This folder may be hidden by the operating system. Read Show hidden files and folders. For example:

Windows XP/2000: C:\Documents and Settings\<username>\Local Settings\Application Data\Mozilla\Firefox\Mozilla Firefox

Windows 7/ Vista: C:\Users\<username>\AppData\Local\Mozilla\Firefox\Mozilla Firefox

Method 2: Download the most recent version of the Firefox setup file from www.mozilla.org/firefox and install it "over the top" of your current Firefox |installation. [4] [5]

See also

Software Update - Software Update not working properly

External links

• Updates reported when running newest version (Firefox Support)

Related bug reports:

• Bug 368661 – on install, remove the updates directory, updates.xml and the active-update.xml file
• Bug 372981 – Update history missing after update to 2.0.0.2
• Bug 374140 – Software Update (Firefox 2001 -> 2002) Problem - wrong User Agents
• Bug 374900 - Update without permissions fails - then gets confused after administrator update
• Bug 375710 – Firefox wants to downgrade to 2.0.0.2 from 2.0.0.3
• Bug 376305 – scenario where the user could get prompted to update to 2.0.0.3 (even though they have 2.0.0.3)