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Firefox messed up after clicking on https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

  • 2 replies
  • 2 have this problem
  • 1 view
  • Last reply by pf7879

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Hello,

I was running high CPU on FirefoxCP Webcontent (and high on fan action), so I tried to do some trouble shooting and followed Firefox's advice and pressed REFRESH on the following website.

https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

Once I did that, I could no longer access any webpage on Firefox. Whatever webpage I try to open, it gives me the message

"Your connection is not secure".

I don't know how to fix that and have to use another browser completely.

Please help as most of my bookmarks and history is non Firefox and I'd like to use Firefox again. I tried trashing Firefox application, downloaded and reinstalled it again but with no luck.

Please advice what to do get Firefox up and running without problems again.

The good thing is: my fans are quiet now.

Pavla

Hello, I was running high CPU on FirefoxCP Webcontent (and high on fan action), so I tried to do some trouble shooting and followed Firefox's advice and pressed REFRESH on the following website. https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings Once I did that, I could no longer access any webpage on Firefox. Whatever webpage I try to open, it gives me the message "Your connection is not secure". I don't know how to fix that and have to use another browser completely. Please help as most of my bookmarks and history is non Firefox and I'd like to use Firefox again. I tried trashing Firefox application, downloaded and reinstalled it again but with no luck. Please advice what to do get Firefox up and running without problems again. The good thing is: my fans are quiet now. Pavla

Chosen solution

Hi Pavla, the most common reason for having this problem after a refresh is that Firefox was previously set up to trust an intermediary and now the trust is broken. Such an intermediary can be:

  • your security software that filters all of your browsing connections
  • a proxy server (more common in a company environment)
  • malware on your system that was reading all of your browsing

Could you take a look at these two articles and see whether you can track down an intermediary:

If none of those programs sounds familiar, you can share the suspicious certificate with forum volunteers. On the error page, if you click the Advanced button, and you have the SEC_ERROR_UNKNOWN_ISSUER code, it's a link. Click that to display a coded version of the certificate, and use the copy button to copy it, and then paste it into a reply.

I typically use this site to decode the certificate and study the "Issuer", in case you want to try it first: https://certlogik.com/decoder/ (and of course there are many others)

Read this answer in context 👍 2

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Chosen Solution

Hi Pavla, the most common reason for having this problem after a refresh is that Firefox was previously set up to trust an intermediary and now the trust is broken. Such an intermediary can be:

  • your security software that filters all of your browsing connections
  • a proxy server (more common in a company environment)
  • malware on your system that was reading all of your browsing

Could you take a look at these two articles and see whether you can track down an intermediary:

If none of those programs sounds familiar, you can share the suspicious certificate with forum volunteers. On the error page, if you click the Advanced button, and you have the SEC_ERROR_UNKNOWN_ISSUER code, it's a link. Click that to display a coded version of the certificate, and use the copy button to copy it, and then paste it into a reply.

I typically use this site to decode the certificate and study the "Issuer", in case you want to try it first: https://certlogik.com/decoder/ (and of course there are many others)

Modified by jscher2000 - Support Volunteer

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Hello, thank you, I figured it out eventually - Avast was the culprit. Disabling "Scan secure connections" in the web shield worked for me. Thank you very much.