I have several accounts and send out on any of them. However, I have one Gmail account and it sends without problems. The others are ATT/Yahoo related. I contacted ATT, there isn't a problem on their side. I can send out mail if I go directly to the account.

I meant to say, "I have several accounts and (I can't send) out on any of them."

No sorry, I am still getting this message when I try to send out email.

"An error occurred while sending mail. The mail server responded: Request failed; Mailbox unavailable. Please verify that your email address is correct in your account settings and try again."

Application Basics Name Thunderbird Version 52.6.0 User Agent Mozilla/5.0 (Windows NT 6.3; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 Profile Folder (Local drive) Application Build ID 20180123185941 Enabled Plugins about:plugins Build Configuration about:buildconfig Memory Use about:memory Profiles about:profiles Mail and News Accounts ID Incoming server Outgoing servers Name Connection security Authentication method Name Connection security Authentication method Default? account1 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account2 (none) Local Folders plain passwordCleartext account3 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account11 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account12 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account17 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account18 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account19 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account20 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account21 (pop3) inbound.att.net:995 SSL passwordCleartext smtp.mail.yahoo.com:465 SSL passwordCleartext true account22 (rss) Feeds plain passwordCleartext account23 (imap) imap.gmail.com:993 SSL OAuth2 smtp.gmail.com:465 SSL OAuth2 true

Subject: sfhowes posted an answer to your question "Sending email error instructs to verify email address. Address is correct and I still can't send out emails." Date: Fri, 9 Feb 2018 00:58:19 +0000 From: Mozilla Support Forum <no-reply@support.mozilla.org> Reply-To: no-reply@mozilla.org To: teresawilde@bellsouth.net

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