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My mac computer says the download Firefox 45.0.1.dmg is not recognized. What do I do?

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  • 2 have this problem
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  • Last reply by cor-el

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Today I tried to download Firefox and after the download was done, I clicked on it to open it. Instead of opening, there was a Warning box that popped up and said, "Firefox 45.0.1.dmg not recognized". This is on my mac computer and I don't know why I can't download Firefox. Someone, please tell me how to fix this. Thanks.

Today I tried to download Firefox and after the download was done, I clicked on it to open it. Instead of opening, there was a Warning box that popped up and said, "Firefox 45.0.1.dmg not recognized". This is on my mac computer and I don't know why I can't download Firefox. Someone, please tell me how to fix this. Thanks.

All Replies (3)

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I'm a Windows person, so the best I can do is point you to this article to see whether anything there helps: How to download and install Firefox on Mac.

If that doesn't work normally, do other .dmg files work?

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I'm not sure. I don't know if I've downloaded other .dmg files before.

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If there a problem with updating or with the permissions then best is to download the full version and trash the currently installed Firefox application to do a clean reinstall.

Download a new copy of the Firefox application and save the Disk Image file to the desktop

Your personal data like bookmarks is stored in the Firefox profile folder, so you won't lose personal data when you uninstall and reinstall or update Firefox, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.

You can try to disable security software temporarily if the problem persists.