Problems checking Yahoo

I have the same issue.  I thought it might be related to 2-step authentication because it never asks for it when I reset profile and cookies.  Also, every time I right click x-notifer icon and select Yahoo, it shows me the login screen even when I logged in manually in the same session.

Indeed I have the same problem. Goes to login despite having orrect passwords. Even tried the new Ff profile.

RpD disabling add-ons also disables x notifier!

Sorry my deleting takes out replies.
Continuing discussion may help you find answers.

I'm having the same issues with Yahoo.  It's grayed out and isn't automatically checking.  When I click on it, it brings me to a login screen instead of straight into my mail.  My gmail and hotmail are working without issue.  Version 3.4.1 here.  I use 2 step authentication.

I have some 15 yahoo email accounts and all work correctly except one(1), which initially logs on(Inbox appears briefly) then the Sign In box reappears, after the second sign in Yahoo mail is normal. This issue started during the past 5 days or so.... I've been using this email configuration for several years.

I've tried reloading xnotifier(3.4.1), dropped back to 3.4 etc. Nothing seems to work to correct the issue.

Some thoughts...
If you manually open a Firefox tab, and go to mail.yahoo.com and login manually, and let FF save your password.... then... perhaps ...when clicking your Yahoo account on X-Notifier's pop-up account list... perhaps, it will simply go into your account and not the login screen.  (If you told FF to -never- save pwds, then you have to fix that, if you want it to try to save pwd.)
- As far as whether X-N will then check for email, I dunno.  You could try a new Firefox profile, load only X-Notifier, create from scratch only your problem yahoo account... to see if it works (checks mail).  If it does, then there's a glitch/conflict in your regular FF profile.  
Then, in your regular profile... I would disable all add-ons except X-Notifier in your regular profile, restart FF, and see if X-N will then check yahoo.
I would delete my account in X-Notifier, restart FF, and redefine it from scratch... and see if X-N can then check yahoo.  If not, then I would export my accounts, delete X-Notifier and let it delete user info, restart FF, re-add X-Notifier, re-add your problem yahoo account from scratch, and see if X-N checks yahoo. If it does, then try importing your accounts.

This troubleshooting is indeed tedious, but becomes necessary when all else fails... particularly when other people's yahoo accounts are being checked just fine in X-Notifier, else the forum would be flooded.  Yes, some of  you/us have problems... I have some problem accounts in Chrome that work fine in FF and Tbird.  Persistence pays off, troubleshooting is a pain, user profiles can get corrupted, etc.  I have given up on my problem accounts in Chrome as I mainly use Thunderbird.

X-notifier has stopped checking my Yahoo emails on Firefox.  It does not indicate when I have a new email or indicate the number of emails.

This has been happening for about a week.  When I click on my email account, it takes me to the main Yahoo logon screen.  When I try to logon manually, I get this message:

"The browser you're using refuses to sign in. (cookies rejected)"

I did nothing to cause this defect and it is very aggravating because I now have to use the Google browser to check my emails.  X-notifier is working properly on Google Chrome.

I had donated to X-notifier because I liked the great add-on  on Firefox.  It is much more user friendly than the way it works on Google Chrome.  Please address this problem and fix it.

I have 2 PCs which use xnotifier, one at home and one at work.  Up until yesterday, the work one was functioning as intended and the home one  is the one I reported on above.  Now both are having the exact same issue (same account).  I'm betting its related to the timing of how long Yahoo will keep you logged in before asking for the pw again.  I think the default is 2 weeks.  RpD may start to see his deluge in the forums soon if that's the case.  Perhaps the developer or someone has an account that the timeout value can be changed to test.

Tried all your thoughts, nothing changed.

I can login fine using Internet Exlorer, Chrome , Firefox manually etc. The issue is only with one(1) of 15 yahoo email accounts where X-Notifier will not check the email address as "Yahoo" asks to login twice. I can see that xnotifier initially logs into the account and the inbox is displayed briefly then it changes to the login screen again. On the second login everything appears normal as far as accessing the inbox. Looked to me like some kind of double authentcation issue buy Yahoo says NO.

Looks like it maybe some kind of xnotifier timing/loop issue whereby it initially logs in then subsequently falls back to the login screen again.  I cannot see anything unusal with this particular email account as it has worked normally for years.

If you won't supply Tobwithu with your existing problem account... then create a brand new Yahoo account as a test and see if it has the same problems.  If it does, then send the login information to xndevel@gmail.com   ...if it works normally for him, it's going to be something glitched on your particular setup.

Please update to X-notifer 3.4.2
http://xnotifier.tobwithu.com/history.php

I did a system restore to June 20th and X-notifier is working.  I knew there was nothing I had done because I keep my computer clean. 

Something either in the latest Firefox update or the X-notifier update is causing this problem.  So I'm not updating either one again.

Let me explain example...

1) Whenever website change their homepage design, sometime change code how to sign-in[login] their email on new interface homepage. Tobwithu need to update script(s) to match on NEW inferface homepage.

2) I am on Firefox BETA, recently Firefox 31 beta FOUR, that cause all my email do NOT work, "need cookie(s)". I did communicate with Tobwithu and he fixed with-in one day on cookie(s) issue.

As you (tanda327) said "So I'm not updating either one again."

My answer "impossbile", because Firefox always update every six (6) weeks, AND sometime webpage new design looks that cause login change code.

That why WE need TOBWITHU, to keep it up and current version, without him we will be #"(<ed , so we are count blessed to have him around on this earth for other 50 years! AND good donation and he will keep it up and support his family and going on, going on.

I tried 3.4.2, but it still exhibits the same behavior.  Yahoo is grayed out in the menu, and if I hover, it says "Yahoo: not checked" in red.  I can click on Yahoo and it brings me to a login that is filled out with my username and password and I have to hit "Signin".  When I'm feeling better, I may try turning off 2 factor authentication and see if this helps or not.

Looks like its fixed in 3.4.3 (see other Yahoo mail thread). Thanks tobewithu.

Thanks, 3.4.3 fixed my Yahoo issue...