In this article we will discuss the Firefox 5 software update error when upgrading from Firefox 4 to Firefox 5. I have already written about the new release of Firefox 5. I was waiting for automatic update of Firefox 5 to be available and today I got the notification that there is a new version of Firefox available and that it is strongly recommended that I upgrade to the latest version. I accepted it and the download started. At the end of the download Firefox needed to restart itself in order for the update to be applied.
I restarted Firefox but it gave the following error:
Software Update Failed
The update could not be installed. Please make sure there are no other copies of Firefox running on your computer, and then restart Firefox to try again.
I restarted Firefox many time but to no avail. I also tried to restart the computer but the same error prevailed.
I have finally come up with a solution to this problem. This problem will come on systems running Windows Vista and Windows 7 with UAC (User Account Control) enabled.
Actually Firefox needs administrative privileges in order to install itself in the default installation directory. There are two solutions to this problem.
1- Run As Administrator
Once you have downloaded the new Firefox 5 and upgraded it and you’re getting the same error as above, you should go to the Start Menu, right click Firefox item and select Run As Administrator. This will immediately trigger the upgrade process and the installation of Firefox 5 will be completed successfully.
2- Change the Installation Folder
This method is suitable for those who are running a clean install of Firefox 5 and not upgrading. You should change the installation folder from the default C:\\Program Files to a folder in any other drive other than C:\\. The installation will complete successfully without running Firefox as administrator.