Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

Mozilla Support में खोजें

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 do I undo a Firefox upgrade that went onto my computer but is incompatible and is now preventing me from accessing the Web?

  • 1 प्रत्युत्तर दें
  • 42
  • 4 views
  • के द्वारा अंतिम प्रतियुतर cor-el

more options

Hello. Please help! I just upgraded from Firefox 3.6.22 to Firefox 4.0 on my Mac PowerBook G4 laptop. I run Mac OS X Tiger 10.4. I did not know that Firefox 4.0 would go onto my computer if it was not compatible. It downloaded and replaced the old version. When I went to open up Firefox, it told me it could not open because the system was incompatible. Now I cannot access the Internet using Firefox, which I prefer to other browsers. How can I go back to my old version of Firefox?

Thank you.

Hello. Please help! I just upgraded from Firefox 3.6.22 to Firefox 4.0 on my Mac PowerBook G4 laptop. I run Mac OS X Tiger 10.4. I did not know that Firefox 4.0 would go onto my computer if it was not compatible. It downloaded and replaced the old version. When I went to open up Firefox, it told me it could not open because the system was incompatible. Now I cannot access the Internet using Firefox, which I prefer to other browsers. How can I go back to my old version of Firefox? Thank you.

All Replies (1)

more options

Firefox 4 versions and later do not run on a PowerPC Mac.

Firefox 4 and later require at least OS X 10.5 and an Intel Mac.

For an unofficial Firefox 6 compatible version (TenFourFox) that runs on PowerPC Macs with OS X 10.4.11 or OS X 10.5.8 you can look at:

Firefox 3.6.x (Mac OS X 10.4 and later) can be found here: