There's a very good chance that those are created by an add-on. Try going to the following page and disabling ALL nonessential extensions. Then restart Firefox and see whether that resolves the issue.

orange Firefox button or classic Tools menu > Add-ons > Extensions category

Edit: Forgot to say: pop-up blockers only work on separate windows, not content inserted into the current page.

Nope, not there. BTW the last one I saw was actually one from Firefox advertising the new build. lol

Now what do I do?

Could you reply with some screen shots? That may help someone recognize the source. There is a "Browse" button below the text compose area to upload images. Also, this might help: How do I create a screenshot of my problem? Please blur, delete, or block any personal information in the screen shots.

Do a malware check with some malware scanning programs on the Windows computer.
You need to scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of their databases before doing a scan.

• http://www.malwarebytes.org/mbam.php - Malwarebytes' Anti-Malware
• http://www.superantispyware.com/ - SuperAntispyware
• http://www.microsoft.com/security/scanner/en-us/default.aspx - Microsoft Safety Scanner
• http://www.microsoft.com/windows/products/winfamily/defender/default.mspx - Windows Defender: Home Page
• http://www.safer-networking.org/en/index.html - Spybot Search & Destroy

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

• http://support.kaspersky.com/viruses/solutions?qid=208280684

See also:

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

I have already done that. The funny part is, earlier this morning Yahoo had a banner and just a few moments ago Toyota had one too. So it is annoying that these entities have gotten around the normal advert pop up using this new skinny, bottom of the page banner.

I am really irritated over this and cannot find anything wrong with any of my programs as you indicate it might be. There HAS GOT TO BE A WAY to stop these things.

Ok I got my first pop up banner just a few moments ago. Just take a look at that logo...Mozilla itself and Yahoo. !!!! What a pain.

See that purple advert banner at the bottom of the page? That is the culprit and some of them are for Facebook, Twitter, etc. This one happens to be for you to upgrade to a faster, better FireFox recommended by Yahoo.

Ok Firefox...Mozilla, what is the deal? You don't have any instructions listing how to prevent these...what is going on?

Someone, please help me. I hate these banners.

Thank you for the lead. Yes, after a few clicks in Yahoo News, I got that promotion, too. The yellow button leads to a page promoting the Yahoo toolbar. On reload, it suggested making Yahoo my home page.

The ad is inserted by a script, so some script blockers might stop the ad. However, using a script blocker such as NoScript is a significant commitment because by default all scripts are blocked and you need to give a lot of approvals so that various websites work correctly. Fortunately, these are available from a right-click menu and do not appear as incessant pop-ups. (And it's very educational seeing how web pages are assembled from so many different servers.)

You could try an extension such as AdBlock Plus and see whether that works; I've never tried it myself.

Bookmarklet - Manual Workaround
A bookmarklet is a script that you save as a bookmark, for convenience, you can save it to the Bookmarks Toolbar.

(1) Copy the following line of code (it's all one long line):

javascript:var d=document.getElementById("adx_al");if(d){d=d.parentNode.parentNode;d.parentNode.removeChild(d);}void 0;

(2) Right-click the Bookmarks Toolbar and choose New Bookmark

(3) Paste the code in as the Location

(4) Name the bookmark as you wish (for example, adx-bye)

If the ad appears, try the button. If the script is consistent, it should remove the ad.

By the way, blocking the script from adinterax.com blocks the ad. Some people use the Windows hosts file to point domains back to the computer to prevent them from loading in all programs (including other browsers). I don't use that method myself, but you can search around for more advice on it if you like.

I just checked out adinterax.com and came up with the following "Untrusted" info:

This Connection is Untrusted

               You have asked Firefox to connect

securely to adinterax.com, but we can't confirm that your connection is secure.

         Normally, when you try to connect securely,

sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.

         What Should I Do?
        
           If you usually connect to

this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.

       adinterax.com uses an invalid security certificate.

The certificate is only valid for www.adinterax.com

(Error code: ssl_error_bad_cert_domain)

I think your request got redirected because it didn't go to an existing page on that server. I didn't note the exact URL and I'm not getting the banner at the moment. Anyway, Yahoo owns the adinterax.com domain so presumably it operates the server as well.

Wouldn't code in userContent.css to hide that #adx_al item work?

• http://kb.mozillazine.org/userContent.css

I'm not seeing that banner, so can't test this.

@-moz-document domain(yahoo.com){ #adx_al { display:none!important; } }

Hiding #adx_al should hide the content of the ad. The container might create a barrier to clicking links in that area, but perhaps that's tolerable.