hello drewid, this can have various reasons. without knowing the url of the site in question it isn't possible to give you targeted advice...

The URL is https://www.maineoptions.org/registration.aspx

hi, thanks. the cert seems to be implemented properly by the site: https://www.ssllabs.com/ssltest/analyze.html?d=maineoptions.org&hideResults=on

can you try the following and see if you can load the site again afterwards?: go to the firefox menu ≡ > help ? > troubleshooting information, click on profile folder/show folder and close all firefox windows afterwards. a windows explorer window should open up - in there rename the file named cert8.db to something like oldcert8.db - it will be regenerated again the next time you launch the browser...

I've tried that twice already, and I'm still having the problem.

when you attempt to add an exception on the bottom of the error page (don't add it for real!) & inspect the certificate (see the screenshot attached for instructions):

• which issuer information does the certificate contain?

You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

• Hold down the Shift key and left-click the Reload button
• Press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
• Press "Command + Shift + R" (Mac)

Clear the cache and remove cookies only from websites that cause problems.

"Clear the Cache":

• Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

• Firefox/Tools > Options > Privacy > "Use custom settings for history" > Cookies: "Show Cookies"

@philipp Issued By Common Name (CN) GeoTrust DV SSL CA - G4 Organization (O) GeoTrust Inc. Organizational Unit (OU) Domain Validated SSL

@cor-el, No, it's not a refresh thing, I've already tried the Shift-Reload thing. I've also already cleared all of this site's cookies. But thanks for the suggestion.

The Nightly build shows this information in Tools > Page Info > General for me on Linux:

Website: www.maineoptions.org
Verified by: GeoTrust Inc.
Technical Details
Connection Encrypted (TLS_RSA_WITH_AES_128_CBC_SHA, 128 bit keys, TLS 1.2)

Do you have a cert_override.txt file in the Firefox profile folder?

You can delete possible user.js and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

• http://kb.mozillazine.org/Preferences_not_saved
• http://kb.mozillazine.org/Resetting_preferences

You can remove all data stored in Firefox from a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History > Show All History" or "View > Sidebar > History") or via the about:permissions page.

Using "Forget About This Site" will remove all data stored in Firefox from that domain like bookmarks, cookies, passwords, cache, history, and exceptions, so be cautious and if you have a password or other data from that domain that you do not want to lose then make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of the involved files.

It doesn't have any lasting effect, so if you revisit such a 'forgotten' website then data from that website will be saved once again.

Sorry I've been away Cor-el and Philipp, I had n emergency, then another thing and...

Anyway, it's working now, and I'm not sure why. I didn't get to trying the things in last reply Cor-el. Maybe the site added the intermediate certs themselves?