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Firefox 4 won't open on my Mac; says it's not compatible with my system (Mac OS4)

Scallegretto
Scallegretto
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I read the system requirements for Firefox 4. My mac should be compatible. I had Firefox 3.6? on my mac. Am running Mac OS 10.4.11. I downloaded Firefox 4; when I tried to install, it said there was a "newer" version of the software on my machine (but it is/was version 3.6) and asked if I still wanted to proceed. I said yes, thinking Version 4 would replace 3.6. Well, it did this. Now, Firefox is in my apps folder, but the icon has a / sign across it and the app won't open up. Just says it cannot open because it is not supported on this system.... Now what do I do? I can't go back to the 3.6 version because I can't find a version of it to download and I can't open 4. Help! How do I get Firefox back on my computer?

I read the system requirements for Firefox 4. My mac should be compatible. I had Firefox 3.6? on my mac. Am running Mac OS 10.4.11. I downloaded Firefox 4; when I tried to install, it said there was a "newer" version of the software on my machine (but it is/was version 3.6) and asked if I still wanted to proceed. I said yes, thinking Version 4 would replace 3.6. Well, it did this. Now, Firefox is in my apps folder, but the icon has a / sign across it and the app won't open up. Just says it cannot open because it is not supported on this system.... Now what do I do? I can't go back to the 3.6 version because I can't find a version of it to download and I can't open 4. Help! How do I get Firefox back on my computer?

All Replies (3)

the-edmeister
the-edmeister
  • Moderator
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4.0 needs 10.5 and an Intel processor.
http://www.mozilla.com/en-US/firefox/4.0/system-requirements/

For older Macs that aren't supported in Firefox 4.0, try TenFourFox for PowerPC's running Mac 10.4.11 & 10.5.8 .
http://www.floodgap.com/software/tenfourfox/

Linda
Linda
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I had this problem too. Just do a google search for firefox 3.6 and download, worked for me with no loss of bookmarks or history. Mozilla should have the requirements posted right next to the download link, so there can be no mistakes and if there is it should warn you that this version will not work on your computer

Scallegretto
Scallegretto Question owner
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Thanks, Lindis -- I was able to bring back 3.6 and it works fine. I agree with you, the system requirements should be posted right next to the download link or at least a link to the system requirements. I couldn't find the system requirements through a link anywhere except on the Firefox Yahoo site, where it said that 4 would work with OS 10.4xx. I now see that somewhere on the Firefox site, there is a system requirements page, but it isn't referenced anywhere on the home page where the 4 download link is and I'm not sure how you get to it. But... I don't need it now, thanks to your input!