Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Appearance/Themes).

• Don't make any changes on the Safe mode start window.

See:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

If it does work in Safe-mode then disable all extensions and then try to find which is causing it by enabling one at a time until the problem reappears.

• Use "Disable all add-ons" on the Safe mode start window to disable all extensions.
• Close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")

I went through the list of things to turn off and check in safe mode, didn't work.

This problem did not start until I "upgraded" from Firefox 3.6 to Firefox 4.0, > had problems with 4.0, >uninstalled 4.0 and reinstalled Firefox 3.6, >problem started.

I have 2 computers here doing the same thing after uninstalling 4.0 and reinstalling 3.6. There is something that did not uninstall when 4.0 was uninstalled. Ver 4.0 did not do a clean uninstall. Whatever is left over is clashing with the 3.6 reinstall.

I haven't changed any add-ons, themes, etc. Just the program files from 3.6 to 4.0, then back to 3.6 again.

Whats going on? Appreciate someone looking into this problem. Thank you

Does that also happens in the text area on this forum?

No it doesn't. It's doing it in Yahoo mail, and e-bay messages. Didn't start until (see previous explanations).

Here's something else I've noticed:

Ver. 3.6 had a different look to it, while Ver. 4.0 has the tool bars and buttons placed differently. The look of the page after uninstalling and reinstalling hasn't changed. It still looks like the ver. 4.0 program even though it's supposed to be the ver. 3.6 program.

Don't get me wrong, I like the new placements, it's just not working correctly.

Thank you.

Corrected problem. Here's how I did it.

Step 1. Go to this site:

ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/3.6.8/win32/en-US/

and download this file:

Firefox Setup 3.6.8.exe (remember where you put this file)

Step 2. Backup bookmarks to a separate file.

Step 3. Write down ALL SAVED PASSWORDS.

Step 4. Run CC Cleaner to clean all excess data.

Step 5. Run CC Cleaner to completely uninstall Firefox.

                 (do not save anything)

Step 6. Open file where you placed the downloaded file:

Firefox Setup 3.6.8.exe

and click "run", then follow the directions for a regular install from there.

Everything's working correctly now. It only took a complete removal of Firefox 4.0 (or whatever was actually in the system after install, uninstall, and reinstall) to stop the original problem. When you guys get Firefox 4 up and running properly, I look forward to upgrading. But, not until it works correctly.

This fix was drastic, but, it worked. Hope this helps somebody else.