Have you run a scan for malware? It might be a good idea.

• SuperAntispyware - http://www.superantispyware.com/
• AdwCleaner - http://www.bleepingcomputer.com/download/adwcleaner/
• Malwarebytes' Anti-Malware - https://www.malwarebytes.org/
• Spybot Search & Destroy - http://www.safer-networking.org/en/index.html
• Kasperky Free Security Scan - http://www.kaspersky.com/security-scan
• Windows Defender - http://windows.microsoft.com/en-us/windows/using-defender

If these don't find it or can't clear it, post in one of these forums for specialized malware removal help:

• http://www.spywarewarrior.com/index.php
• http://www.spywareinfoforum.com/
• http://bleepingcomputer.com/
• http://www.thespykiller.co.uk/index.php?board=3.0
• http://forums.whatthetech.com/index.php?showforum=27ßß

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

   Anti-rootkit utility TDSSKiller:

• http://support.kaspersky.com/5350?el=88446

In addition to using automated cleanup tools, I suggest:

(1) Open the Windows Control Panel, Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help surface undisclosed bundle items that snuck in with some software you agreed to install. Be suspicious of everything you do not recognize/remember, as malware often uses important or innocent sounding names to discourage you from removing it. Take out as much trash as possible here.

(2) Open Firefox's Add-ons page using either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons
• in the Windows "Run" dialog, type or paste
  firefox.exe "about:addons"

In the left column, click Plugins. Set nonessential and unrecognized plugins to "Never Activate".

In the left column, click Extensions. Then, if in doubt, disable (or Remove, if possible) unrecognized and unwanted extensions.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

If the infection will not allow you to access the Add-ons page:

Try Firefox's Safe Mode. That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

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).

In Safe Mode, extensions are already disabled, but you can remove unwanted ones.

Media Player is just a player. It starts when it is called. And sometimes, it's a popup that calls it.

Flash block {web link} Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way, but if you want to see it, just click on it

Adblock Plus {web link} Blocks annoying video ads on YouTube, Facebook ads, banners and much more. Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).

Adblock Plus Pop-up Addon {web link} Adblock Plus Pop-up Addon extends the blocking functionality of Adblock Plus to those annoying pop-up windows that open on mouse clicks and other user actions.

Forum; Adblock Plus Homepage {web link}