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Getting box saying "Cannot guarantee authenticity of the domain to which encrypted connection is established (blah blah) certificate not up to date.

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  • 最近回覆由 FredMcD

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This is about Firefox not from Firefox. Seems to originate from Entrust.net which I never applied for. Trouble started after I downloaded Windows 10 and caught a bunch of trouble from Yahoo, then tried to update Java and got extra sneaky stuff with it. I use Kaspersky, which is apparently sending the message about you and they have taken over my computer trying to fix everything for several hours yesterday and today but still getting the message that Firefox certificate is basically expired. Whatever a certificate is. BTW box with message is still up in the corner, don't know if you can see it.

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You may have ad / mal-ware. Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.


Let’s do a full clean re-install; Download Firefox For All languages And Systems {web link} Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86)

Mac: Open the "Applications" folder.
https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory.

Do Not remove the profiles folder.

Look for, and rename any Mozilla or Firefox program folders by adding .old to them. Do not rename the Mozilla Thunderbird folder if there is one.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. If all goes well, remove the OLD folders when you are done.


If there is a problem, start your Computer in safe mode and try again.

Starting The Computer In Safe Mode;
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