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updated today to v 56.0.1 64 bit--all/most sites get error: unsecur connection. what's up with that?

JimJinNJ
JimJinNJ
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many of my sites give error message: Your connection is not secure

"The owner of mail.google.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.

This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate.

Learn more…

Report errors like this to help Mozilla identify and block malicious sites"

so I can't get to gmail and other standard sites. can I downgrade to previous FF version?

many of my sites give error message: Your connection is not secure "The owner of mail.google.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate. Learn more… Report errors like this to help Mozilla identify and block malicious sites" so I can't get to gmail and other standard sites. can I downgrade to previous FF version?

All Replies (4)

philipp
philipp
  • Moderator
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hi, a downgrade won't help here. first please make sure that the date, time & timezone are set correctly on your system. if this doesn't solve the issue (or it is already set properly), a solution depends on the individual circumstances:

  • what is the error code shown when you click on advanced on that error page?
  • please also give us more information about the error by clicking on the error code, copying the text to the clipboard and then pasting it here into a reply in the forum like shown in the screenshot.

thank you!

JimJinNJ
JimJinNJ Question owner
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I fixed it by using something I found on Youtube. involved clearing cache and changing proxy settings. I have no ideas how it fixed it but I find this kind of thing a good reason to not do updates.

Rob.Hindle2009
Rob.Hindle2009
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Below is the message I get - and similar for any site I visit. I can access Gmail (and other web sites) OK in other browsers. The owner of mail.google.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate. Screen grab attached

  • FF is version 58.0.1, Windows 10, 64 bit
  • As there are suggestions that a Security product could be interfering I disabled the Kaspersky add-in to FF - problem remains
  • I tried restart FF in safe mode without plugins - problem remains
  • I tried Firefox Refresh (reset to defaults) - problem remains
  • Uninstalled FF and reinstalled a fresh download - problem remains
  • The problem became evident after a PC reboot and I think a new version of FF was loaded at the same time.
  • FF developer version is working OK.
  • FF on a second PC (also 58.0.1, Windows 10, 64 bit with Kaspersky security) is OK so not a local network problem
  • It MAY be a problem with the PC but the only program affected is FF, a full system scan with Kaspersky comes up clean.

Google finds others reporting the same issue over several years.

Rob.Hindle2009
Rob.Hindle2009
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I eventually found the fix here: https://support.mozilla.org/en-US/kb/what-does-your-connection-is-not-secure-mean

remove cert9.db

Pity so many seem to be having the same problem and so hard to find the fix.