Check the status of Yahoo Mail.
If Yahoo Mail is down, wait and check back until the status changes.
Check that Caps Lock isn’t on.

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Yahoo passwords are case-sensitive, so ifCaps Lockis on, whatever you bang out won’t work.
If it was on, turn it off and enter again.
Yahoo displays an emblem in the password field that shows ifCaps Lockmode is active.
sign on through the email-specific page.
Do this when themain Yahoo login siteis problematic.
Confirm that your password is correct.
Select theeye-shapedicon in the password field to see what you’re typing.
Get a fresh start if none of the passwords you remember work.
Quit and restart the net web client.
wipe the web client’s cookiesorclear the cache.
Try a different online window.
Programs don’t necessarily handle opening the same site the same way.
Yahoo might have made some changes behind the scenes that make it function better on some browsers than others.
These messages usually come with a number (for example, Temporary Error 8).
Still, these typically point to surfing app incompatibility or a data issue.
If you get one of these error messages, these three fixes should work most of the time.
Enable (or disable) your Yahoo Account Key.
The Account Key feature lets you authorize a Yahoo sign-in on your phone instead of entering a password.
If your password doesn’t work on the web, activate a key to bypass it.