Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

How can I remove the 4.0.1 update and return to 3.5 update? My school website will not let me use 4.0.1?

  • 1 cavab
  • 31 have this problem
  • 4 views
  • Last reply by TonyE

more options

I updated with 4.0.1 and am no longer able to connect to my school website without a message letting me know this new update is not supported. They are still supporting 3.5. I have updated before and it didn't seem to be a problem. I attend Colorado Christian University. I have called them, but I would like to return to 3.5. How can I remove 4.0.1?

Thank you

I updated with 4.0.1 and am no longer able to connect to my school website without a message letting me know this new update is not supported. They are still supporting 3.5. I have updated before and it didn't seem to be a problem. I attend Colorado Christian University. I have called them, but I would like to return to 3.5. How can I remove 4.0.1? Thank you

All Replies (1)

more options

If you downgrade to Firefox 3.5 you will lose user data such as history and cookies. If you downgrade to Firefox 3,6 you will not lose this data.


To downgrade to Firefox 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.

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