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!

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

Natao arisiva ity resaka mitohy ity. Mametraha fanontaniana azafady raha mila fanampiana.

I have downloaded the new Firefox 4 on Mac OS X, getting message that I cannot use this version of Mac OS X and cannot get back open old 3.6.10 format either since it has been replaced. How can I get this to work or replace previous application?

  • 1 valiny
  • 7 manana an'ity olana ity
  • 9 views
  • Valiny farany nomen'i cor-el

more options

Downloaded Firefox 4 to replace 3.6.10 but cannot open. Message says application will not work with Mac OS X. Can I return to old version or is something incompatible in new Firefox 4?

Downloaded Firefox 4 to replace 3.6.10 but cannot open. Message says application will not work with Mac OS X. Can I return to old version or is something incompatible in new Firefox 4?

All Replies (1)

more options

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

For Mac OS X 10.4.11 or Mac OS X 10.5.8 you can look at:

Firefox 3.6.x can be found here: