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I just downloaded the new version of Firefox and now every site I used to use such as Facebook, Twitter, and Youtube show "This Connection Is Untrusted"

  • 5 replies
  • 3 have this problem
  • 2 views
  • Last reply by FredMcD

DBoyPChase
DBoyPChase
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I just downloaded the new version of Firefox and now every site I used to use such as Facebook, Twitter, and Youtube show "This Connection Is Untrusted". Even when I do accept the risks the site no longer looks the way it's looked for years. Twitter doesn't even give me the option to accept the risks at all and shows this error (Error code: sec_error_unknown_issuer). I've tried resetting Firefox, I've checked the time and date, and I've removed and added Firefox to see if that would work. Nothing seems to be working so I can see the sites the way they normally would be instead of "coded". Can anybody help me please?!!! Thanks

I just downloaded the new version of Firefox and now every site I used to use such as Facebook, Twitter, and Youtube show "This Connection Is Untrusted". Even when I do accept the risks the site no longer looks the way it's looked for years. Twitter doesn't even give me the option to accept the risks at all and shows this error (Error code: sec_error_unknown_issuer). I've tried resetting Firefox, I've checked the time and date, and I've removed and added Firefox to see if that would work. Nothing seems to be working so I can see the sites the way they normally would be instead of "coded". Can anybody help me please?!!! Thanks

All Replies (5)

philipp
philipp
  • Moderator
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hello DBoyPChase, a possible solution depends on different factors.

please visit a site like https://www.youtube.com/ and attempt to add an exception (don't add it for real!) on the bottom of the error page & inspect the certificate - see the screenshot attached for instructions:

  • which issuer information does the certificate contain?
DBoyPChase
DBoyPChase Question owner
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Here's an example of how things look when I try to log onto Facebook, Twitter, or Yahoo. Even when I do accept the risks it looks weird like it's being "coded" or the original version is being blocked.

philipp
philipp
  • Moderator
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ok, unfortunately the fiddler2.com 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

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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If you wouldn't mind, open the Windows Control Panel, Uninstall a Program and, after the list loads, click the "Installed on" column heading to view recent additions. Particularly if you got an unofficial download, there may have been bundled items.

FredMcD
FredMcD
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Separate Issue; Update your Shockwave Flash v15.0.0.152 http://get.adobe.com/shockwave/