Send & Receive Basics If you can receive but not send then you have a bad SMTP configuration If you can send but not receive you have a bad POP or IMAP configuration You can try re-entering info. You can delete account and create a new one. (not just delete the data but the account) Using copy/paste can result in an extra space being added. Type carefully. Check your Keychain for corruption. Check under advanced . . .
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