These are the official instruction from yahoo:
To set up IMAP on your mobile device please use these settings:
Incoming Server - imap.mail.yahoo.com
Outgoing Server - smtp.mail.yahoo.com
Incoming Port - 993 (requires SSL)
Outgoing Port - 465 (requires SSL/TLS)
Username: full email address (for example,
bill@yahoo.com or
bill@rocketmail.com)
Password: the password you login to Yahoo! with.
I have also tried these and they have worked too:
Incoming IMAP Mail ServerSetting :
User Name :
user@yahoo.com
Password : your email password
Incoming Mail Server : imap.n.mail.yahoo.com
Mail Box Name : Yahoo IMAP
Mail Box Type : IMAP
Security (Port) : Off
Port : Default (143)
Outgoing IMAP Mail ServerSetting :
Email Address :
user@yahoo.com
User Name :
user@yahoo.com
Password : your email password
Outgoing Mail Server : smtp.mobile.mail.yahoo.com
Security (Port) : Off
Port : 587