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prefs.js -- malware inserted

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  • Last reply by James

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The Firefox prefs.js file was quarantined by avast yesterday. Message indicated malware had infected the file. Now when I click on the Firefox icon the MSN browser comes up. How can I get back to using Firefox safely? Can I uninstall Firefox, then re-install it to make the problem go away?

The Firefox prefs.js file was quarantined by avast yesterday. Message indicated malware had infected the file. Now when I click on the Firefox icon the MSN browser comes up. How can I get back to using Firefox safely? Can I uninstall Firefox, then re-install it to make the problem go away?

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^Ignore the above reply by donthavecow

https://support.mozilla.org/en-US/questions/1371864

For some Firefox (and Thunderbird) users who use Avast or AVG briefly had these scanners quarantine the prefs.js file even though Avast/AVG said they fixed the False Positive issue the day before.

If you still have the prefs.js file you can out it back in your Profile.