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Why won't firefox load websites after reseting to default state

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  • 1 has this problem
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  • Last reply by philipp

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I've reset mozilla through the tools troubleshooting and reset fire fix to its default state. Now the webpages such as facebook, hotmail won't load or they won't load properly.

A window with this connection is untrusted appears. Even when I validate a security exception it won't load and it won't let me have an option of validating sometimes. Technical details says invalid security certificate. No issuer chain provided. Error code unknown issuer.

I've reset mozilla through the tools troubleshooting and reset fire fix to its default state. Now the webpages such as facebook, hotmail won't load or they won't load properly. A window with this connection is untrusted appears. Even when I validate a security exception it won't load and it won't let me have an option of validating sometimes. Technical details says invalid security certificate. No issuer chain provided. Error code unknown issuer.

Chosen solution

unfortunately the fiddler2 issuer in certificates might be a sign of unwanted software present on your pc that is intercepting secure network traffic. please go into the system control panel and uninstall programs like BrowserSafeguard, BrowserSafe, SafeGuard or other software that sounds suspicious and didn't get installed by you intentionally.
reference: https://support.mozilla.org/en-US/questions/982532#answer-520145

afterwards, run a full scan of your system with different security tools like the free version of malwarebytes & adwcleaner.

Troubleshoot Firefox issues caused by malware

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hello, a possible solution depends on different factors - in case the error code equals sec_error_unknown_issuer, please attempt to add an exception on the bottom of the error page & inspect the certificate (see the screenshot attached for instructions):

  • which issuer information does the certificate contain?

thank you!

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Common Name: DO_NOT_TRUST_FiddlerRoot Organisation: DO_NOT_TRUST Organisation Unit: Created by http://www.fiddler2.com

That's who it is issued by.

Technical details say: Connection Encrypted: High Grade Encryption (TLS_RSA_WITH_128_CBC_SHA,128 bit keys)

Seems to not open FB and windows live hotmail.

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Chosen Solution

unfortunately the fiddler2 issuer in certificates might be a sign of unwanted software present on your pc that is intercepting secure network traffic. please go into the system control panel and uninstall programs like BrowserSafeguard, BrowserSafe, SafeGuard or other software that sounds suspicious and didn't get installed by you intentionally.
reference: https://support.mozilla.org/en-US/questions/982532#answer-520145

afterwards, run a full scan of your system with different security tools like the free version of malwarebytes & adwcleaner.

Troubleshoot Firefox issues caused by malware

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Thanks heaps mate. All solved.

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you're very welcome :))