Are you able to access Yahoo mail through a different web browser, like Internet Explorer? To open Internet Explorer, click on the "Start" button in the bottom left corner of your computer screen, and then type the name "Internet Explorer" in the search box that appears.

I have this same problem. Got back access by starting firefox in safe mode. Not sure yet which add-on is causing the problem, but one seems to be blocking access to all https sites (Yahoo email is one of them).

To restart without add-ons Firefox>Help>Re-start with add-ons disabled....

This answer did sort of solve my issue. I have use of my e-mail thru internet explorer-but-would like to go back to Firefox-don't see it anywhere on screen. Do I need to totally shut down internet explorer to get back to Firefox?Thank you for getting me this far!! I can't access my yahoo mail going back thru the Firefox-help-restart with add-ons disabled. Am I forever stuck using internet explorer? If so,I guess I'll adapt & change my toolbars back to how I want them{don't like these}. Any more suggestions? Need all the help I can get!!

This is still an open issue. Can anyone else lend a hand?

Sorry to hear that. My problem was solved by disabling add-on CSFire (for anyone who reaches this post).

Here is another recent post with a similar issue. Adding it here so you can check to see if that person gets a better reply. https://support.mozilla.com/en-US/questions/869703

For me the issue was that something was stopping me from accessing secure sites (https://websites). You might check to see if this is the case for you as well. I believe yahoo has an http://website entry.

Wish you luck because I know this is frustrating.

I have the same problem can't figure it out, in the meantime I installed IETab and got it to work that way, it's not a permanent solution but for now it's an option

STILL NO FIREFOX!!! ABLE TO GET MAIL/SOME THINGS BY GOING THROUGH INTERNET EXPLORER. WOULD MUCH RATHER GETTING FIREFOX BACK!!! ANYONE HAVE ANY SUGGESTIONS?

I am on a mac and had this problem as well. I fixed it by disabling all my addons. I will go back and activate each and see which caused the problem when I have more time, but can open mail and that's a start.

That internet explorer suggestion was a good idea. the one that mbrubeck posted.

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