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

  • 3 replies
  • 1 has this problem
  • 5 views
  • Last reply by Xircal

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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.

Chosen solution

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.

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All Replies (3)

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Chosen Solution

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.

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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.

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You're welcome.