Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More
Open

Error message

Kevin Naughton

When I login into Thunderbird, I continue getting the following error message "Login to server imap.comcast.net with username kfn.appraiser@comcast.net failed". I put in correct password and happens again. Mail server is Comcast. Running Windows 11

When I login into Thunderbird, I continue getting the following error message "Login to server imap.comcast.net with username kfn.appraiser@comcast.net failed". I put in correct password and happens again. Mail server is Comcast. Running Windows 11

All Replies (1)

Here are my working Comcast server settings (I use IMAP). How do they compare with yours?

IMAP (Incoming): Incoming Server Type: IMAP Mail Server Incoming Server Name: imap.comcast.net Port: 993 User Name: <my email address> Connection Security: SSL/TLS Authentication method: OAuth2

POP3 (Incoming): Incoming Server Type: POP Mail Server Incoming Server Name: pop3.comcast.net Port: 995 User Name: <my email address> Connection Security: SSL/TLS Authentication method: OAuth2

SMTP (Outgoing): SMTP Server Name: smtp.comcast.net Port: 465 Connection Security: SSL/TLS Authentication method: OAuth2 User Name: <my email address>

This matches Comcast's own recommended settings as found here:

https://www.xfinity.com/support/articles/email-client-programs-with-xfinity-email

EXCEPT that they don't mention OAuth2 for authentication. They seem to have implemented it sometime in the last year without telling their users, though last time I checked, both it and Normal Password worked... but that could have changed in the meantime. A long-winded way of asking, what is your Authentication Method, OAuth2 or Normal Password?

Some possible remedies depend on your answer to that question, so let us know what you find and we'll take it from there.

One thing to check now is whether cookies are allowed. See <Settings | Privacy | Web Content | Accept cookies from sites>.

Uliza swali

You must log in to your account to reply to posts. Please start a new question, if you do not have an account yet.