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

Cuireadh an snáithe seo sa chartlann. Cuir ceist nua má tá cabhair uait.

I use some software that is not compatible with FF 4. Am I able to download an earlier version and delete FF4?

  • 3 fhreagra
  • 1 leis an bhfadhb seo
  • 5 views
  • Freagra is déanaí ó Xircal

more options

I have software that is not compatible with FF4. I would like to go back to an earlier version of FF. Perhaps 3.x. Is this possible and how would I do this if it is. This will probably be a short term situation until the software is updated for compatibility.

I have software that is not compatible with FF4. I would like to go back to an earlier version of FF. Perhaps 3.x. Is this possible and how would I do this if it is. This will probably be a short term situation until the software is updated for compatibility.

Réiteach roghnaithe

To revert to the previous secure version which is 3.6.17, please do the following:

  1. Go to Download Firefox v3.6.17 and download it to the desktop.

  2. Then go to Add/Remove Programs, scroll down to "Mozilla Firefox" and remove it, choosing to keep your bookmarks, customizations etc., (don't checkmark the box).

  3. Then reboot and delete the folder called "Mozilla Firefox" at this location: C:\Program Files\Mozilla Firefox

  4. Finally run the installation file you downloaded to the desktop earlier.

Your bookmarks, customizations etc., are maintained in a different location and will become available to you again once you complete the installation.


After you complete the installation, please go to the Plugins Check page and update where necessary.

Read this answer in context 👍 0

All Replies (3)

more options

Réiteach Roghnaithe

To revert to the previous secure version which is 3.6.17, please do the following:

  1. Go to Download Firefox v3.6.17 and download it to the desktop.

  2. Then go to Add/Remove Programs, scroll down to "Mozilla Firefox" and remove it, choosing to keep your bookmarks, customizations etc., (don't checkmark the box).

  3. Then reboot and delete the folder called "Mozilla Firefox" at this location: C:\Program Files\Mozilla Firefox

  4. Finally run the installation file you downloaded to the desktop earlier.

Your bookmarks, customizations etc., are maintained in a different location and will become available to you again once you complete the installation.


After you complete the installation, please go to the Plugins Check page and update where necessary.

more options

Xircal; Thanks for the response. Apologize for not responding earlier. Took a few days to have the time to actually take action. Worked perfectly. Thank you again.

more options

You're welcome.