This error code doesn't come up here often. When it does, it seems to be a settings or data issue, because when users create a fresh profile (either using Refresh or completely from scratch), they don't get the error any more.

So it's surprising that Refresh did not work for you. Did you connect to a Firefox Sync account after the Refresh to import any old settings?

Setting up a new profile can be a lot of work (if you are a heavy customizer), but testing one without customization is pretty easy:

New Profile Test

This takes about 3 minutes, plus the time to test your problem sites.

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

Click the Create a New Profile button, then click Next. Assign a name like Oct2018, ignore the option to relocate the profile folder, and click the Finish button.

After creating the profile, scroll down to it and click the Set as default profile button below that profile, then scroll back up and click the Restart normally button. (There are some other buttons, but please ignore them.)

Firefox should exit and then start up using the new profile, which will just look brand new. Please ignore any tabs enticing you to connect to a Sync account or to activate extensions found on your system so we can get a clean test.

Do your problem sites work any better in the new profile?

When you are done with the experiment, open the about:profiles page again, click the Set as default profile button for your normal profile, then click the Restart normally button to get back to it.

still the same issue with creating new profile

Is this problem only with Yahoo mail?

Do you know whether any programs filter your web connection, for example, security software or a proxy server?

For example, you could inspect a sample certificate to see whether that points to a "man in the middle." Here's how:

On this page on Mozilla Support, call up the Certificate Viewer using the Page Info dialog. Either:

• right-click (on Mac Ctrl+click) a blank area of the page and choose View Page Info > Security > "View Certificate"
• (menu bar) Tools > Page Info > Security > "View Certificate"
• click the padlock or "i" icon in the address bar, then the ">" button, then More Information, and finally the "View Certificate" button

Normally, the "Issued By" section lists Common Name: Amazon these days, because this server is hosted on AWS (Amazon Web Services). What does yours say?

its hosted by amazon the one that's not working page info has nothing only General and Media no certificate also i did disable the security still the same . i have to check something i guess win10 update might have done something my chrome browser IE all work except Mozilla also how can i can disable win 10 update permanently as i always disable it from services.msc still does it ?

i also did uninstall the update from win10 still same .

i fixed it i uninstalled the whole thins and downloaded it works now

eddie4770 said

i fixed it i uninstalled the whole thins and downloaded it works now

Thanks for the update!

That was very good work. Well done. Please flag your last post as Solved Problem so others will know.