Firefox won't do anything. At all.

Question

Updated Firefox, now it won't do anything. Webpages won't load, don't even get the "connecting..." message, no error messages, nothing. Literally nothing happens when I click on a link, type in a URL & hit enter, try to visit something in my history, etc. Other browsers work, internet connection itself is fine, Firefox works fine on my other computer...........
I've been through all the Mozilla Support articles, searched the forums, etc. Tried everything that I've found - checked the settings on my firewall, various about:config options, antivirus program, etc., made sure "work offline" isn't checked, disabled addons, restarted & reinstalled, etc., and generally checked all the usual suspects. Nada. Made no difference.
Any ideas/advice/suggestions/etc.? Thanks!

Answer 1

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.
*Download the full Firefox installer and save the file to the desktop<br>https://www.mozilla.org/en-US/firefox/all.html
If possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.
*Do NOT remove "personal data" when you uninstall your current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including data in profiles created by other Firefox versions.
Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.
*(32 bit Windows) "C:\Program Files\Mozilla Firefox\"
*(64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"
*It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.
*http://kb.mozillazine.org/Uninstalling_Firefox
Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.
If you keep having problems then also create a new profile.
*http://kb.mozillazine.org/Profile_folder_-_Firefox
*http://kb.mozillazine.org/Profile_backup
*http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall
Do a malware check with several malware scanning programs on the Windows computer.
Please scan with all programs because each program detects different malware.
All these programs have free versions.
Make sure that you update each program to get the latest version of their databases before doing a scan.
*Malwarebytes' Anti-Malware:<br>http://www.malwarebytes.org/mbam.php
*AdwCleaner:<br>http://www.bleepingcomputer.com/download/adwcleaner/<br>http://www.softpedia.com/get/Antivirus/Removal-Tools/AdwCleaner.shtml
*SuperAntispyware:<br>http://www.superantispyware.com/
*Microsoft Safety Scanner:<br>http://www.microsoft.com/security/scanner/en-us/default.aspx
*Windows Defender:<br>http://windows.microsoft.com/en-us/windows/using-defender
*Spybot Search & Destroy:<br>http://www.safer-networking.org/en/index.html
*Kasperky Free Security Scan:<br>http://www.kaspersky.com/security-scan
You can also do a check for a rootkit infection with TDSSKiller.
*Anti-rootkit utility TDSSKiller:<br>http://support.kaspersky.com/5350?el=88446
See also:
*"Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked
*https://support.mozilla.org/kb/troubleshoot-firefox-issues-caused-malware