Who is your eMail provider, the part after the @ sign?
In Mail's Window Menu, choose Connection Doctor, any red dots for status, if so what is the message?
Then click the Show Details button & Check again.
The issues may or may not be connected, let's work on Mail first.
Hi, thanks for replying!
email provider: btinternet (BT yahoo)
Connectin doctor: logging onto the BT server is good (green dot)
Logging onto the SMTP account failed: verify that username and password are correct.
But I am using the same password as I use to access webmail so I know it is correct.
The Password rejection can confuse people since it's a catch all meaning...
This Password, Username, Authentication method... is not recognized on this Port to this Server, or a server end problem.
If using a browser to login via WebMail works it's not Name or Password, but one of the other ones.
The receiving email ports are:
IMAP is port 143
IMAP-SSL is port 993
POP is port 110
POP-SSL is port 995
Outgoing ports are...
SMTP and SMTP-SSL is on ports 25, 587 and 465. Port 587 has to be SSL, and port 465 is enforced TLS-wrapped and is generally used by Outlook users.