The issue can only be resolved if you have used the correct POP and IMAP settings in Yahoo.

POP settings for Yahoo Mail

• Incoming Mail (POP) Server

• Server - pop.mail.yahoo.com

• Port - 995

• Requires SSL - Yes

Outgoing Mail (SMTP) Server

• Server - smtp.mail.yahoo.com

• Port - 465 or 587

• Requires SSL - Yes

• Requires TLS - Yes (if available)

• Requires authentication – Yes

You can match your settings with the…