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Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.office365.com timed out. Try again.

GerrySnyder
GerrySnyder
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For Thunderbird: I can receive e-mails. Error on sending. Message below. Output settings were fine last week. This is affecting several people at Kansas State University. With Pegasus e-mail, extending the timeout to 90 seconds seems to work. Can the timeout be extended in Thunderbird?

Error Message: Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.office365.com timed out. Try again.

Thanks.

For Thunderbird: I can receive e-mails. Error on sending. Message below. Output settings were fine last week. This is affecting several people at Kansas State University. With Pegasus e-mail, extending the timeout to 90 seconds seems to work. Can the timeout be extended in Thunderbird? Error Message: Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.office365.com timed out. Try again. Thanks.
Attached screenshots

All Replies (3)

sfhowes
sfhowes
  • Top 10 Contributor
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Is there a security program scanning outgoing mail or controlling SSL connections? The timeout is set by the mailnews.tcptimeout preference in Config. editor, but the default is already 100 sec.

sfhowes
sfhowes
  • Top 10 Contributor
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Is there a security program scanning outgoing mail or controlling SSL connections? The timeout is set by the mailnews.tcptimeout preference in Config. editor, but the default is already 100 sec.

GerrySnyder
GerrySnyder Question owner
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The problem was fix on our end. Our campus has been hit with several phishing scams that triggered our connection to smtp.office365.com to be blocked. Forces that be unblocked this problem. Thanks for the feedback. It's good to know of the 100 sec. timeout.