Please provide screenshots of the errors you are getting. Is this an IMAP or POP account? Are you running Thunderbird on a computer, Mobile, Tablet or something else (please specify)? Which version of Thunderbird are you using? Which Operating System are you using?

IMAP 128.6.1 desktop pc windows 10

IMAP 128.6.1 desktop pc windows 10

Spectrum mail client settings are published here:

https://www.spectrum.net/support/internet/spectrum-email-server-settings

But the specific settings for charter.net are much clearer here:

https://www.postbox-inc.com/setup/email-settings/access-charter-net-via-imap-smtp

Make sure you've set up the outgoing (SMTP) server in Thunderbird according to those settings. Post back with a screenshot of your settings and of the error message you get if that still doesn't work.

entered settings as indicated by you. still no fix

I told you to post a screenshot of your settings and of the error message you get if it still doesn't work…