If you downgrade to Firefox 3.5 you will lose all browsing history and cookies. If you downgrade to 3.6 you will not lose this data.

To downgrade to Firefox 3.5 or 3.6 first uninstall Firefox 4, but do not select the option to "Remove my Firefox personal data". If you select that option it will delete your bookmarks, passwords and other user data.

You can then install the latest version of Firefox 3.6 available from http://www.mozilla.com/en-US/firefox/all-older.html - it will automatically use your current bookmarks, passwords etc.

If you need to go to 3.5, you can get the latest version of Firefox 3.5 from http://releases.mozilla.org/pub/mozilla.org/firefox/releases/3.5.18/win32/en-US/

To avoid possible problems with downgrading, I recommend going to your profile folder and deleting the following files if they exist - extensions.cache, extensions.rdf, extensions.ini, extensions.sqlite and localstore.rdf. Deleting these files will force Firefox to rebuild the list of installed extensions, checking their compatibility, and reset toolbar customizations.

For details of how to find your profile folder see https://support.mozilla.com/kb/Profiles

Thank you! Thank you! Thank you!!! You're a life-safer!!! Now, how do I go about un-installing Firefox 4.0??? Is there a certain link you can send me to that gives me that information? If so, that would be great! I can un-install programs, in a jiff, or upgrade... but, this is kind of out of my league, here...

Thank you, again!

See https://support.mozilla.com/kb/uninstalling+Firefox

4.0 is un-installed, 3.6 is installed and all is working fabulous!!

Thank you so much for the help!!!

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