Just to confirm, the same problem occurs whether you approach email using the traditional link or through the Mail icon on the Yahoo home page? Sometimes old links are not redirected correctly when servers are reconfigured, so we always suggest this double-check.

When you have a problem with one particular site, a good "first thing to try" is clearing your Firefox cache and deleting your saved cookies for the site.

(1) Clear Firefox's Cache

See: How to clear the Firefox cache

If you have a large hard drive, this might take a few minutes.

(2) Remove the site's cookies (save any pending work first). While viewing a page on the site, try either:

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

In the dialog that opens, you can remove the site's cookies individually.

Then try reloading the page and logging in again. Does that help?

Thank you for the prompt reply. I went to the "how to" page you suggested and set things up to clear the cache accordingly. Tried to log in to my e-mail accounts again and no dice. Still stops after entering the password. Mozilla crashed when I shut things down. I went to the gym to take out some frustrations. Fired things up just now and still no dice. Plan B?

Montivigant said

Thank you for the prompt reply. I went to the "how to" page you suggested and set things up to clear the cache accordingly. Tried to log in to my e-mail accounts again and no dice. Still stops after entering the password. Mozilla crashed when I shut things down. I went to the gym to take out some frustrations. Fired things up just now and still no dice. Plan B?

Gym is good ! :=} May need to go back again... I have 4 Yahoo accounts and never had your problem so with that being said please delete all your cookies from Yahoo again and clear your cache (good habit to know) use the "basic url " to get to mail: after have disabled any cookie/ad blockers http://mail.yahoo.com

As said have no issues with the new Yahoo login though it is slower and a pain.."The browser you're using refuses to sign in. (cookies rejected)" The page I got above from has the old Yahoo login....Please let us know what happens... https://login.yahoo.com/config/verify

Thanks for the update.

Did you also try removing your Yahoo cookies?

If those two things do not help, could you test in Firefox's Safe Mode? In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement? (More info: Diagnose Firefox issues using Troubleshoot Mode)

Apologies for the delay.... Just followed the directions to clear cache, setting same to do so automatically, and also removed cookies. X'd out of Mozilla and started it back up again. Tried to log into each of my business/personal accounts. I was successful with one but the other two exhibited the *same problem where things come to an abrupt stop when I enter my p/w.* I can try safe mode but I may be getting past my pay grade.... I've been using Mozilla for 15 years or so with nary a hickup. Not sure what has changed betwixt Mozilla and Yahoo e-mail.

I only have one Yahoo! account so I don't think I can test that out.

If you launch a private window (Ctrl+Shift+p) to open the second Yahoo account, will it open there? That would be a way to isolate it from the cookies that were just set for the first account, as well as cached files from that session.

If that helps... There is an extension designed to isolate accounts between tabs or between windows so that you can use them simultaneously. I wonder whether even if you don't use them simultaneously, opening them in this artificially separated way might help?

https://addons.mozilla.org/firefox/addon/multifox/