Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove Firefox and any leftover program files and then reinstall Firefox. Please follow these steps one by one:

1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu) and confirm all upcoming messages.
3. Now, uninstall Firefox by following the steps mentioned in the Uninstall Firefox article.

IMPORTANT: On Windows, the uninstaller has the option to remove your personal data and settings. Make sure that you do not check this option; otherwise all of your bookmarks, passwords, extensions, user customizations and other Firefox user profile data will be removed from your computer.

After uninstalling Firefox on Windows, delete the "Mozilla Firefox" program folder, located by default in one of these locations:

• (On 32-bit Windows) C:\Program Files\Mozilla Firefox
• (On 64-bit Windows) C:\Program Files (x86)\Mozilla Firefox

1. Go to the Windows Start menu and click on "Computer".
2. In the Explorer window that opens, double click Local Disk (C:) to open the C:\ drive.
3. Find the "Program Files (x86)" folder or "Program Files" folder.
   • On 32-bit Windows, double-click the Program Files folder to open it.
   • On 64-bit Windows, you will see a "Program Files (x86)" folder AND a "Program Files" folder. Open the Program Files (x86) folder.
4. Look for a Mozilla Firefox folder. If you find one, right-click it and select Delete and confirm that you want to move the folder to the Recycle Bin.

Now, go ahead and reinstall Firefox:

1. Double-click the downloaded installation file and go through the steps of the installation wizard.
2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Please report back to see if this helped you!

Can you attach screenshots for comparison?

• http://en.wikipedia.org/wiki/Screenshot
• https://support.mozilla.org/kb/how-do-i-create-screenshot-my-problem

Use a compressed image type like PNG or JPG to save the screenshot.

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

• Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

• Tools > Options > Privacy > Cookies: "Show Cookies"

here are the screen shots of Yahoo on Firefox and IE. Never tried this before, hope you can read it.

Thanks

The first screenshot from Firefox shows that you are logged on the the Yahoo! site and the IE screenshot shows the basic page when you are not signed on.

Do you still have a difference when you are logged on in IE as well or if you are signed off in both cases?

I must be looking at something different, but on the IE page it show me logged in. My name is in the right hand corner. Doesn't that mean I am logged in?? Anyway, I am still getting 2 different types of Yahoo home page. I logged out of Firefox and it still shows the new? Yahoo homepage. When this all started, I did not change anything. Just woke up one morning and there it was.

If I am not mistaken, Yahoo configures this on purpose so that the Yahoo website's performance is better.

I tried doing the whole uninstall reinstall, STILL HAVE PROBLEM is there really NO solution? Also tried the whole clear cache thing too...Nada help at all.

same thing happened to me, and yup signed in and everything... tried a system restore etc, no luck