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NXFilter and HTTPS security certificates blocking access to websites with newest version

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Websites like my webmail with Yahoo which worked fine with the last version of Firefox all of the sudden have no access. Not only does it list it as not having a current security certificate, but it does not let me put it in as an exception. Come on, this is Yahoo mail, for ATT worldnet email. Twitter also is giving me an expired certificate without the ability to add the exception. What is going on.

And all of the sudden, with this update, any web address I put in is blocked with something I never loaded called Nxfilter. I can't find it to uninstall it in my control panel or in revo uninstaller, yet it is stopping access to websites. I can't get onto facebook,

None of this happened until I updated my firefox, so I have to conclude it is caused by Firefox. How do I operate in this environment. I may have to change browsers but I don't want to. I have been using Firefox since you were a new browser and did not want to change to a different browser. But right now, the browser is tying my hands!

Websites like my webmail with Yahoo which worked fine with the last version of Firefox all of the sudden have no access. Not only does it list it as not having a current security certificate, but it does not let me put it in as an exception. Come on, this is Yahoo mail, for ATT worldnet email. Twitter also is giving me an expired certificate without the ability to add the exception. What is going on. And all of the sudden, with this update, any web address I put in is blocked with something I never loaded called Nxfilter. I can't find it to uninstall it in my control panel or in revo uninstaller, yet it is stopping access to websites. I can't get onto facebook, None of this happened until I updated my firefox, so I have to conclude it is caused by Firefox. How do I operate in this environment. I may have to change browsers but I don't want to. I have been using Firefox since you were a new browser and did not want to change to a different browser. But right now, the browser is tying my hands!

All Replies (2)

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Hello,

The Refresh feature (called "Reset" in older Firefox versions) can fix many issues by restoring Firefox to its factory default state while saving your bookmarks, history, passwords, cookies, and other essential information.

Note: When you use this feature, you will lose any extensions, toolbar customizations, and some preferences. See the Refresh Firefox - reset add-ons and settings article for more information.

To Refresh Firefox:

  1. Open the Troubleshooting Information page using one of these methods:
    • Click the menu button New Fx Menu, click help Help-29 and select Troubleshooting Information. A new tab containing your troubleshooting information should open.
    • If you're unable to access the Help menu, type about:support in your address bar to bring up the Troubleshooting Information page.
  2. At the top right corner of the page, you should see a button that says "Refresh Firefox" ("Reset Firefox" in older Firefox versions). Click on it.
  3. Firefox will close. After the refresh process is completed, Firefox will show a window with the information that is imported.
  4. Click Finish and Firefox will reopen.

Did this fix the problem? Please report back to us!

Thank you.

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Firefox does not include NxFilter, but you may see various software bundles advertised on search engines that include third party software.

If this is a company computer, I would check with your IT on whether this is something you are required to use. If not, I would investigate it as potential malware.

(1) Open the Windows Control Panel, Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help surface undisclosed bundle items that snuck in with some software you agreed to install. Don't be fooled by seemingly innocent or important names if you do not remember choosing to install them. Take out as much trash as possible here.

(2) You can search for remaining issues with the scanning/cleaning tools listed in our support article: Troubleshoot Firefox issues caused by malware. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.

Any luck?