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Suddenly unable to send emails from Thunderbird (but can receive them)

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  • Last reply by schlefer

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Hi --

Thunderbird was working fine. Perhaps because it updated (but I'm not sure), I suddenly became unable to send emails, though I can still receive emails. Tried changing my password, and the same problem occurred (can receive, can't send). Tried disabling Kaspersky antivirus and firewall, and the same problem occurred.

Mail provider: Microsoft outlook—outlook.office.com (provided through MIT) Antivirus/firewall software: Kaspersky Operating system: Windows 10 Thunderbird version: 78.5.1 (32-bit)

I'm attaching a screenshot of my STMP settings.

Help! Any ideas?

Thanks, Jonathan

Hi -- Thunderbird was working fine. Perhaps because it updated (but I'm not sure), I suddenly became unable to send emails, though I can still receive emails. Tried changing my password, and the same problem occurred (can receive, can't send). Tried disabling Kaspersky antivirus and firewall, and the same problem occurred. Mail provider: Microsoft outlook—outlook.office.com (provided through MIT) Antivirus/firewall software: Kaspersky Operating system: Windows 10 Thunderbird version: 78.5.1 (32-bit) I'm attaching a screenshot of my STMP settings. Help! Any ideas? Thanks, Jonathan
Attached screenshots

Chosen solution

Try to start Windows in safe mode with networking enabled.

Does the problem go away?

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Chosen Solution

Try to start Windows in safe mode with networking enabled.

Does the problem go away?

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Thanks, Christ1. I should have marked it solved earlier. For some unknown reason, without my doing anything else, in a couple of days the problem went away. Go figure. In any event, I appreciate your message. Jonathan