Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

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

I switched from Internet Explorer to Firefox and was so happy. Then I took the prompt and converted to Firefox 4.0 and now my computer is so slow it is almost unbearable. How do I switch back to Firefox 3 or some earlier version to get my speed back?

  • 2 பதிலளிப்புகள்
  • 7 இந்த பிரச்னைகள் உள்ளது
  • 2 views
  • Last reply by alan_r

It takes a long time for the computer to warm up and start working, maybe 30 seconds. Just to open an email can take 10 seconds. This is the kind of delay I was experiencing on Internet Explorer before I switched to Firefox 3. It is particularly slow if I am opening a photo attachment. It also can be slow just moving from one tab to another. Help!

It takes a long time for the computer to warm up and start working, maybe 30 seconds. Just to open an email can take 10 seconds. This is the kind of delay I was experiencing on Internet Explorer before I switched to Firefox 3. It is particularly slow if I am opening a photo attachment. It also can be slow just moving from one tab to another. Help!

All Replies (2)

Credit Tony E: 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. See https://support.mozilla.com/kb/Uninstalling+Firefox 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

Better to try and fix Fx4; you'll struggle to catch up from Fx3 with Fx5 looming. Try Safe Mode(hold Shift key down as you double-click on Firefox icon) and see if an add-on or hardware acceleration is causing the problem. Look up Problematic Extensions. Make sure Plug-ins such as Flash are up to date.

Disable third-party toolbars. Delete Firefox from your Firewall so it will need a new approval.

Firefox isn't the only thing that has been updated and new conflicts can develop.