Hmm, that tab is a little confusing. The Exceptions list is not specifically for third party cookies.

I think this is how it is supposed to work: let's say you are on mail.google.com. Firefox calls cookies from mail.google.com first party cookies. If content embedded in the page is from another server, say, ads.example.com, then any cookies from ads.example.com would be third party cookies. So if you block third party cookies, you would normally only get cookies from the sites whose names appear in the address bar.

But I want to focus on this part:

I keep clicking off this bothersome windows and they another browser window even though I've set "Open new windows in a new tab instead.

Are you having a problem with pop-up ads? Pop-up ads usually are generated by scripts in the page -- or by bad add-ons -- and cookie settings have no effect on those. Could you describe the pattern of the problem in more detail?

I have a YouTube channel so as long as I'm signed in no pop-ups but recently if I open a search in YouTube on another tab all kind of pop-ups appear that literally block my viewing of the page. when I try to close them they take me to another site or open another window (not tab). Furthermore most help forums on this topic deal with this problem but don't acknowledge the fact that Google and Yahoo also do this practice. Thanks for your help.

Hmm, that's a little extreme. Could you test in Firefox's Safe Mode? In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement with the Youtube ads situation? (More info: Diagnose Firefox issues using Troubleshoot Mode)

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