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Authentication Failed, must login..

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  • Èsì tí ó kẹ́hìn lọ́wọ́ user01229325

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I am unable to send emails. I keep receiving this failed message " 5.7.1 [R8] Authentication Failed, must login.." I contacted my cable provider and they are at a loss. I have tried everything but with no luck. My operating system is Microsoft 10. Hope you can help.

I am unable to send emails. I keep receiving this failed message " 5.7.1 [R8] Authentication Failed, must login.." I contacted my cable provider and they are at a loss. I have tried everything but with no luck. My operating system is Microsoft 10. Hope you can help.

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Post your Thunderbird troubleshooting info. From the Help Menu select Troubleshooting Information. Copy to Clipboard Come back here and paste into a reply window