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Suddenly can't send mails because can't connect to SMTP-Server

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Hi everybody,

since two days ago I am unable to send mails from thunderbird via my hotmail account, because thunderbird can't connect smtp.live.com. There was no change I recall that could have triggered the problem (i.e. I didn't update thunderbird or anything else) and it has been working perfectly fine for years before that. Receiving messages works fine.

I checked all the steps in the "Cannot send message"-support post (https://support.mozilla.org/en-US/kb/cannot-send-messages), but that didn't change the problem nor did I get closer to the solution.

I use a hotmail.com mail-account, thunderbird version 91.5.1 (64-bit) on macOS HighSierra (10.13.6). A screenshot of the server settings is attached.

Any help on how to solve the problem would be highly appreciated.

Thanks! Franca

Hi everybody, since two days ago I am unable to send mails from thunderbird via my hotmail account, because thunderbird can't connect smtp.live.com. There was no change I recall that could have triggered the problem (i.e. I didn't update thunderbird or anything else) and it has been working perfectly fine for years before that. Receiving messages works fine. I checked all the steps in the "Cannot send message"-support post (https://support.mozilla.org/en-US/kb/cannot-send-messages), but that didn't change the problem nor did I get closer to the solution. I use a hotmail.com mail-account, thunderbird version 91.5.1 (64-bit) on macOS HighSierra (10.13.6). A screenshot of the server settings is attached. Any help on how to solve the problem would be highly appreciated. Thanks! Franca

Chosen solution

Your picture doesn't appear, because pictures aren't allowed on a user's first post.

My Hotmail account works with these settings:

incoming outlook.office365.com on port 993 (IMAP) or 995 (POP), SSL/TLS, normal password; outgoing smtp.office365.com on 587, STARTTLS, normal password. User Name = email address. An app password is required if two-step verification is set on the account. For POP, POP must be enabled in hotmail webmail settings.

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Chosen Solution

Your picture doesn't appear, because pictures aren't allowed on a user's first post.

My Hotmail account works with these settings:

incoming outlook.office365.com on port 993 (IMAP) or 995 (POP), SSL/TLS, normal password; outgoing smtp.office365.com on 587, STARTTLS, normal password. User Name = email address. An app password is required if two-step verification is set on the account. For POP, POP must be enabled in hotmail webmail settings.

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Thanks so much for your fast reply and your help. I used to have smtp.live.com as outgoing server, as it is listed on the german "thunderbird and hotmail"-configuration page. Not sure why that one stopped working. But glad that the smtp.office365.com works just fine. So all good. Thanks again!

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It seems like the good folks at Microsoft made a change without bothering to do any kind of wide-area announcement. The attached screenshot is from the Help screen that comes up when your enter "SMTP settings" in the Help search bar when in the browser version of Outlook Live.