Does your internet provider use a proxy? Try checking out this [https://support.mozilla.org/en-US/kb/advanced-panel-accessibility-browsing-network-upda#w_connection-settings-dialog Page]

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 install 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 ---- 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

Type '''about:preferences#advanced'''<Enter> in the address bar. Under '''Advanced,''' Select '''Network.''' Look for '''Configure How Firefox Connects''' and press the '''Settings''' button. Check the settings.

Tried ":about:preferences#advanced"....the 'Use system proxy settings' was selected.... and now what? ------------------------- We have Norton IS...none of the articles discussed Norton.

''johngracebw [[#answer-691463|said]]'' <blockquote> Tried ":about:preferences#advanced"....the 'Use system proxy settings' was selected.... and now what? </blockquote> Unless you are using a proxy, this should be '''None.''' <blockquote> We have Norton IS...none of the articles discussed Norton. </blockquote> Some added toolbar and anti-virus add-ons are known to cause Firefox issues. '''Disable All of them.'''