Post a screenshot of your outgoing (SMTP) server settings, so we may verify they're correct.

Read the following article in the meantime to see possible causes of the problem:

https://support.mozilla.org/kb/cannot-send-messages

In particular, if you're using a VPN, disable it and see whether that makes the problem go away. If it does, check whether your VPN has an option called split tunneling which would allow you to let Thunderbird bypass the VPN.

VPN is off.

According to the following page, the security setting should be STARTTLS, not SSL/TLS:

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

That's strange because I can send and receive email on my phone and through spectrums/roadrunners webmail site with the SSL setting but thunderbird doesnt allow only the SSL setting.

Despite that I made the changes to STARTTLS and now get the following error message that spectrum/roadrunner couldn't help me with. I found this page but don't understand it.....

https://www.spectrum.net/support/internet/understanding-email-error-codes

image attached of new error message.

Thanks for your help.

You have to look in the page you linked for the error with number 1130:

The IP address you’re trying to connect from has an issue with the Domain Name System. Spectrum requires a full circle DNS for emails to be allowed through. Verify the IP you’re connecting from, and check the IP address to ensure a reverse DNS entry exists for the IP. If the IP address is a Spectrum-provided email address, contact us.

Sounds like a VPN issue to me…

Ok I got it to work :)

It was a combination of not having the setting of STARTTLS correct (even though spectrum told me I only need the SSL setting for smtp) and my VPN was turned on. I did have it turned off yesterday but did a reboot of my system and Mcaffee automatically enables it upon sartup. I didn't realize that till you mentioned the VPN settings again.

Thanks again for all your help. If you didn't show me that link for roadrunner settings I would have never known to try that setting, especially after speaking with my provider and having them tell me otherwise.