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firefox seems to be dying

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Firefox stopped loading facebook a few weeks back and I've been using Edge for FB. Today Firefox gives "SEC_ERROR_BAD_SIGNATURE" for a large number of sites, including gmail and all the google sites, while still working for other sites like BBC News. I get the impression that Firefox is being somehow "targeted"... I've used it for years, going back to its predecessors in the 90s and have resisted changing browser so far!

Firefox stopped loading facebook a few weeks back and I've been using Edge for FB. Today Firefox gives "SEC_ERROR_BAD_SIGNATURE" for a large number of sites, including gmail and all the google sites, while still working for other sites like BBC News. I get the impression that Firefox is being somehow "targeted"... I've used it for years, going back to its predecessors in the 90s and have resisted changing browser so far!

All Replies (3)

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First, don't panic :) Usually this happens when antivirus software tamper with web security. What antivirus or internet security software do you use?

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Web search: https://www.bing.com/search?q=SEC_ERROR_BAD_SIGNATURE


There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connection certificates and send their own.

https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can

https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites

https://support.mozilla.org/en-US/kb/secure-connection-failed-error-message

https://support.mozilla.org/en-US/kb/connection-untrusted-error-message

Websites don't load - troubleshoot and fix error messages

http://kb.mozillazine.org/Error_loading_websites

What do the security warning codes mean

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Thanks for these replies. The laptop is supplied by employer for work and I do not have admin rights. It has ESET antivirus running. However, I asked our IT guy about ESET and he said the problem would just go away by itself after 24 hours or so, and it did! Except that facebook still will not let me log in with Firefox. So I still don't know what the problem was, and I'm still using Edge for facebook...