SMTP Error: 501 5.1.3 Bad recipient address syntax on empty Config.adminEmail · Issue #230 · dereuromark/cakephp-tools · GitHub
With email in outbox: Failed to send some messages. Negative SMTP reply 501 5.1.3 Bad recipient address syntax · Issue #1328 · k9mail/k-9 · GitHub
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Unable to send or receive messages for an email account. Errors sending and eliminating them to send a test e-mail
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