I can imagine that constantly getting this error message is becoming annoying. I would like to assist!
Just a couple of questions first; when adding the email account, did you add using the Yahoo link or by selecting “Other”? If you used the Yahoo option, it may not be saving the Username or Password content. It has been suggested to add using the “Other” option. If so, here are the credentials you’ll need to add the Yahoo account:
Username MUST include @yahoo.com
Incoming server = imap.mail.yahoo.com
Outgoing server = smtp.mail.yahoo.com
Try this & let me know how it works out for you!
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