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Thunderbird does not always send email first time

  • 2 replies
  • 1 has this problem
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  • Last reply by sj.mcquay

sj.mcquay
sj.mcquay
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When I try to send an email from Thunderbird sometimes it succeeds and sometimes it does not. Trying again sometimes works and sometimes fails again. It may take many attempts to get a message to send.

The "Sending Message" dialog box gets replaced by a "Send Message Error" dialog box saying, "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp-mail.outlook.com timed out. Try again. OK"

Thunderbird version: 115.9.0

SMTP Server: Description: Office365 (Microsoft) Server Name: smtp-mail.outlook.com Port: 587 Connection security: STARTTLS Authentication method: OAuth2

Operating system: Windows 10.0.19045 Build 19045 ISP: BT Broadband Antivirus software: AVG AntiVirus Free 24.1.8821.822

Please advise on how I can get all my messages to be sent successfully first time. Thank you.

When I try to send an email from Thunderbird sometimes it succeeds and sometimes it does not. Trying again sometimes works and sometimes fails again. It may take many attempts to get a message to send. The "Sending Message" dialog box gets replaced by a "Send Message Error" dialog box saying, "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp-mail.outlook.com timed out. Try again. OK" Thunderbird version: 115.9.0 SMTP Server: Description: Office365 (Microsoft) Server Name: smtp-mail.outlook.com Port: 587 Connection security: STARTTLS Authentication method: OAuth2 Operating system: Windows 10.0.19045 Build 19045 ISP: BT Broadband Antivirus software: AVG AntiVirus Free 24.1.8821.822 Please advise on how I can get all my messages to be sent successfully first time. Thank you.

Chosen solution

Use smtp.office365.com for the server name, keeping other settings the same, and outlook.office365.com for the incoming. Disable the Mail Shield in AVG, or remove it and use the built-in Windows Security.

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sfhowes
sfhowes
  • Top 10 Contributor
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Chosen Solution

Use smtp.office365.com for the server name, keeping other settings the same, and outlook.office365.com for the incoming. Disable the Mail Shield in AVG, or remove it and use the built-in Windows Security.

sj.mcquay
sj.mcquay Question owner
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Thanks for your reply. Incoming was already set as outlook.office365.com. Changing smtp.office365.com for the server name did not seem to have any effect. However, when I disabled the AVG Antivirus Mail Shield my next few messages all went first time. (Not sure what it's doing chewing over short outgoing messages which contain no links and no attachments to be checked.) As a modification to your suggestion, I have just unticked "Scan outbound emails (STMP)" rather than disable Mail Shield completely. Thanks again.

Modified by sj.mcquay