This may be because you are don't have administrative privileges. Please log onto admin account in windows and install the update. Or try downloading the latest version from mozilla.

I have just upgraded to Version 4. It was inadvertently the Yahoo Version so I have now disabled the unwanted add-on. But when I start Firefox I get a large window alert mid screen saying 'that it is recommend strongly that I apply an urgent update'. The more information link fails to work. Installing the Update appears to work in that Firefox registers that it is down loading and installing but the next time I start Firefox I get the same window and repeating process does the same.

What is the urgency and is Firefox's security compromised?

Thanks.

First remove firefox 4 completely from your PC and Then try downloading the latest normal version from here. And Install it.

I have this problem too. Mine is with version 5.0 I get a popup every time I reload the browser, stating that the update failed to install and to please make sure there are no other open Firefox windows open. I know in my case that the problem is caused by administrative privileges. If I right click the Firefox desktop icon and select run as administrator, the update will install. However, I don't want the update. I am a daily Mafia Wars Zynga player, and Firefox version 6 is not compatible with the Zynga Mafia Wars toolbar. I already changed my Firefox options not to automatically download updates and to ask me what I want to do with the ones already downloaded as opposed to auto install. However that darn popup about the update not installing continues to appear every time I start the browser!

Software Update

• http://kb.mozillazine.org/Software_update

Check and tell if its working.