See this article form more information on downgrading to an obsolete version of Firefox:

http://kb.mozillazine.org/Go_back_to_an_old_version_of_Firefox

Thanks for replying. I'm not having any problems right now because I haven't upgraded to 10.0. It took a long time but I finally worked out all the bugs with 9.0 so I'm gun shy. As I said, I've had problems with Norton, most specifically running the toolbar, several times when upgrading and, judging by the number of posts on the subject, so have many others. I'm sorry if my post was not clear. I tried to be very specific. My post stated I want to know how to revert to an older version (ie: 9.0) IF I have problems after upgrading to 10.0. This is an attempt at a preemptive plan. I'll just upgrade to 10.0 and if I have problems with it I'll just use IE until Firefox gets the kinks worked out. Thanks again for replying.

Thanks for your reply. I followed the link and clicked on another link under paragraph 1..."download the version you want"...which led me to a link listing all the previous versions. I clicked on 9.0 but that link only led me to a series of folders that led nowhere. None of the folders open to a download link or an .exe file. I've decided just to suck it up and upgrade to 10.0. If I have problems with Norton again I'll just use IE until Firefox works out the kinks. I just don't want to wrestle with it for days and weeks like I did with 9.0. Thanks again for your help.

Try to make sure that you use the latest Norton updates. Firefox updates themselves are often done for security reasons.

drofdar, You wrote,
I followed the link and clicked on another link under paragraph 1..."download the version you want"...which led me to a link listing all the previous versions. I clicked on 9.0 but that link only led me to a series of folders that led nowhere.

You must have gotten lost somewhere :) I went to http://kb.mozillazine.org/Go_back_to_an_old_version_of_Firefox where it says,
1. Download the version you want from ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/

I had no problem finding both 9.0,

• ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/9.0/win32/en-US/Firefox%20Setup%209.0.exe

... and 9.0.1:

• ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/9.0.1/win32/en-US/Firefox%20Setup%209.0.1.exe

Just so you know, if you do have issues with the Norton Toolbar, it is most likely due to the fact that Norton hadn't updated their toolbar to work with the Newest version of Firefox. Unfortunately with third-party toolbars like that, you often have to wait for them to play catch up.

Try reading this forum thread:

https://support.mozilla.org/en-US/questions/916527

Thanks everyone for all your replies. I was able to download the 9.0.1 from Alice Wyman's second post.

I sucked it up and went to 10.0. As I expected (yes, I'm a pessimist) none of the Norton addons would work. I followed all the steps suggested at the Norton site but still wouldn't work.

Norton has a live chat so I took a gamble. The tech tried all the same things I already tried then told me we would have to uninstall and reinstall Norton IS. That solved the problem.

Thanks again everyone!