Firefox is a browser. It doesn't have a login function. Do you see that message simply by launching Firefox?

yes it pops up before my homepage comes up and I have to click yes or no.

Do you have the popup blocker enabled in the Tools | Options Content menu? See Block popups

Just downloaded Firefox 4 and had hard time finding options. Seems like I do have popup windows blocked. If I unblock it will this go away?

No, you should keep it enabled. It should prevent this from happening.

The company mentioned in your post title appears to be legitimate, so I don't think you've indavertently installed a browser hijacker somehow.

But you mentioned in the beginning that you always had to "logon" to Firefox? Where exactly? Are you the only user?

I shouldn't have said that when I log on. I meant when I open firefox. I am the only user.

Ah..OK.

Try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. Do you see the popup when you do that? If it fails to appear in that configuration, then one of your add-ons is the culprit.

I started it with addons disabled which is safe mode, right? It still popped up.

I got a message that you answered again but I don't see another answer....

The mystery deepens. I didn't respond before this.

Can you go to http://www.malwarebytes.org/ and download the free version. Update it first before you run a full system scan.

ok, I downloaded malwlarebytes.org but it didn't give me an option to update it. It just startedd running a full scan. Says it found 1,857 Errors, Junk Status is in yellow and security status is good. It has a button to fix errors....

Are the errors contained in a submenu called Quarantine? It should look like the one you see in the screenshot I just uploaded.

No submenu called Quarantine.

It's beginning to sound like you've got some kind of malware on your system which is blocking access to the site I gave you and has downloaded a ficticious version of Malwarebytes instead. This is quite common because hackers are aware you'll try to go to security site and download a program to remove their rogue app.

The Malwarebytes program doesn't have a "Junk" filter, but does have a menu called Quarantine as you can see from my screenshot. Also, it doesn't autorun.

What's the file called which you downloaded?

ARO 2011 Trial Version

and I just let it fix some of my problems but it wanted me to buy it to fix the other thousand or so. I hope I haven't infected my computer or that my anti virus, anti malware, etc would catch such a thing.

This program doesn't have anything to do with Malwarebytes. So are you saying you went to the link I gave you and somehow or other you got redirected to ARO 2011?

I just tried the download link @ http://www.malwarebytes.org/ myself, but just get a mirror for that particular app.

yes. I went to the link that you suggested and downloaded it.

I went to Malwarebytes.org and clicked on download free version. That took me to CNET download.com where I downloaded it.

EDIT Our posts got crossed. I just read the last one you posted. So you were redirected to CNnet. But still, you should have been offered the file you see in the screenshot.