I downloaded latest versionof Firefox from Mozilla web page, I rebooted my computer. The update did not take effect. How make late version active ?

Question

My present version of Firfox is 3.5.15
My Op. System is Linux Fedora version 12.
Two days ago when I opened a file in a web search for Mercury Scientific Thermometers, the web page for NovaTech International-USA opened.
Centered in the middle of the page was a screen message reading
"Error: form not found." There's an X in the upper right corner of this small screen. There's an "OK" within the screen. Clicking on either of those optons does nto close the small screen. AND, clicking on any Menu
choice at the top of the main screen produces no action. File Edit View History Bookmarks tools Help are all unresponsive. The screen is
locked to the Cursor and Clicking any menu item. Tho' there are many choices on the Screen for various types of thermometers no choice responds to a click.
I closed down the computer. ThenI did a Cold Boot. There was no
change in the situation described above. The screen appeared again if
I chose to open Firefox.
I use 8 virutal screens. By which I mean I can have 8 screens open at a time. All 7 of my other available screens are perfectly active and perfectly normal in their behavior.
Rebooting changes nothing---the unwanted frozen/locked screen appears again if I attempt to open Firefox.
I opened the Firefox website. I soon found how to download the latest version of Firefox. But I used YUM to download it. Here is an excerpt of the Yum process:
[William@WilliamsComputer ~]$ su
Password:
[root@WilliamsComputer William]# yum install firefox
Loaded plugins: presto, refresh-packagekit
adobe-linux-i386 | 951 B 00:00
updates/metalink | 2.8 kB 00:00
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package firefox.i686 0:3.5.15-1.fc12 set to be updated
--> Processing Dependency: xulrunner >= 1.9.1.15 for package: firefox-3.5.15-1.fc12.i686
--> Running transaction check
---> Package xulrunner.i686 0:1.9.1.15-1.fc12 set to be updated
--> Finished Dependency Resolution
Skipping here much of the YUM processing.
Note the finishing YUM statement:
Dependency Updated:
xulrunner.i686 0:1.9.1.15-1.fc12 Complete!
[root@WilliamsComputer William]# exit
[William@WilliamsComputer ~]$
I did a cold reboot of my computer.
In the Downloads Folder The Firefox update appeared.
But when I opened a Firefox page and clicked Help-About Firefox
the version of Firefox was still 3.5.15 AND the unwanted, Locked,
Frozen Novatech-International---USA Screen was still present and still
locked.
Please teach me the preferred way to Update Firefox and once the Updates have been downloaded, how do I activate those updates?
Many, many thanks,
William
Florida

Answer 1

It is possible that your security software (firewall, anti-virus) blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.
Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.
See:
*https://support.mozilla.org/kb/Server+not+found
*https://support.mozilla.org/kb/Firewalls
*https://support.mozilla.org/kb/fix-problems-connecting-websites-after-updating