Hello Kash_champ, try Google Public DNS IP addresses as a test :

for IPv4 :

• 8.8.8.8
• 8.8.4.4

for IPv6 :

• 2001:4860:4860::8888
• 2001:4860:4860::8844

https://developers.google.com/speed/public-dns/docs/using

any luck ?

thanks

I use 8.8.8.8 Google public DNS as my primary DNS.

Plus I think DNS resolve problem will effect all the browsers. I'm not sure though.

It is possible that your firewall or other security software 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.

• https://support.mozilla.org/kb/troubleshoot-firefox-issues-caused-malware

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:
  http://www.malwarebytes.org/mbam.php
• AdwCleaner:
  http://www.bleepingcomputer.com/download/adwcleaner/
  http://www.softpedia.com/get/Antivirus/Removal-Tools/AdwCleaner.shtml
• SuperAntispyware:
  http://www.superantispyware.com/
• Microsoft Safety Scanner:
  http://www.microsoft.com/security/scanner/en-us/default.aspx
• Windows Defender:
  http://windows.microsoft.com/en-us/windows/using-defender
• Spybot Search & Destroy:
  http://www.safer-networking.org/en/index.html
• Kasperky Free Security Scan:
  http://www.kaspersky.com/security-scan

You can also do a check for a rootkit infection with TDSSKiller.

• Anti-rootkit utility TDSSKiller:
  http://support.kaspersky.com/5350?el=88446

See also:

• "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked

Same problem reported in this thread, also a Kaspersky user (unsolved): https://support.mozilla.org/questions/1092299

jscher2000 said

Same problem reported in this thread, also a Kaspersky user (unsolved): https://support.mozilla.org/questions/1092299

Thank you very much.

I tried disabling 'scanning of encrypted connections' in Kaspersky. That seemed to have stopped the problem temporarily. I re-enabled it, but unfortunately the problem has returned.

I'm planning on taking this issue with Kaspersky. If I get an explanation or solution from them, I'll post it back here.

For, the time being would you please walk me through the processes of importing / installing a root certificate in firefox. [ By the way I checked and there is a "Kaspersky Anti-virus Personal root certificate" already present in my firefox Certificate authorities.]

Thank you very much for the help.

Hi Kash_champ, if you already have the Kaspersky cert in your Authorities, and you aren't getting SSL errors everywhere, I suggest not rocking that boat for the time being.

After having a communication with Kaspersky, they confirmed that it was a reported / known issue that occurs because of some security database updates.

They told me that a future database update would probably solve the problem which luckily for me did solve the problem.

Thanks for all the support.