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Firefox disappeared after Windows 10 update

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After the last Windows 10 Update Firefox seems gone from my PC.

In Program Files (x86) I still have:

Mozilla FirefoxOld Mozilla Firefox.bak Mozilla Firefox.bak.delete

There is also a desktop folder Old Firefox Data

How can I get back my old bookmarks and passwords? And how can this happen?

After the last Windows 10 Update Firefox seems gone from my PC. In Program Files (x86) I still have: Mozilla FirefoxOld Mozilla Firefox.bak Mozilla Firefox.bak.delete There is also a desktop folder ''Old Firefox Data'' How can I get back my old bookmarks and passwords? And how can this happen?

All Replies (3)

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Have you already tried reinstalling the latest version of Firefox? You can grab the installer from:

https://www.mozilla.org/en-US/firefox/all/#product-desktop-release

Normally the Firefox installer will detect that you already have Firefox data and re-use it. Does that work automatically for you?

Note: Old Firefox Data is created when you use the Refresh feature within Firefox. You can check inside to see how long ago that happened by looking at the Last Modified dates on the files.

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I did install the latest FF. It's didn't detect anything.

Then I did the firefox.exe -P, which lets me switch profiles, and all data is back.

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Thank you for reporting back. For future reference, you also can use the about:profiles page to test out what is in other profiles without having to keep closing Firefox. More info in this article: Recover lost or missing Bookmarks.