I can not access my Rocketmail account using MS Outlook 2016

I have finally resolved it as follows:

1) Disable the Yahoo account key, then enable allow using less secure apps.

2) In the User Information fields, insert 'Your Name' and full 'Email address '

3) In the Server Information fields,  choose 'IMAP', insert 'imap.mail.yahoo.com' for incoming mail server, and insert 'smtp.mail.yahoo.com' for outgoing mail server.

4) In the Login Information fields, insert full email address as 'user name ' and your Rocketmail account password as 'Password', check 'Remember password'.

5) Check 'Require logon using Secure Password Authentication  (SPA)'

6) Click 'More settings, and on 'Outgoing Server ' tap check 'My outgoing server  (SMTP) requires authentication '

7) On 'Advanced ' tap, insert 993 and SSL for incoming server, and insert 587 and TLS for outgoing server. Click Ok then Next.

8) Wait for sometime till the process of adding your rocketmail account is completed. 

MISSION ACCOMPLISHED.