unable to get emails

https://support.mozilla.org/en-US/kb/cannot-receive-messages

there's a lock symbol on the email folder - WHY? How do I get rid of it?

The lock symbol indicates a secure connection to the server. This is what you want.

server does not support RFC 5746, see CVE-2009-3555

You can ignore that. The message about CVE-2009-3555 is meant for administrators to make them aware that they need to fix their servers. https://wiki.mozilla.org/Security:Renegotiation

Thanks. Still not sure why I was not getting email that was on the server.....

I am still not getting my email through Thunderbird. Can anyone else help?

Do you get any error message?

Please post your Troubleshooting Information. At the top right of the Thunderbird window, click the menu button , then select Help > Troubleshooting Information. Press the Copy text to clipboard button and paste the information into your reply.

no error messages. I have two accounts for Thunderbird (both under charter.net) What I am finding is the one account that I am getting mail straight away is listed as pop3 and the other one (with a charter address) is imap. It's the imap account that sometimes doesn't load my email or when it does, it takes hours.

Name Thunderbird Version 38.7.2 User Agent Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.7.2

Please post your Troubleshooting Information.