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Very Fast Send Mail SMTP Failure Popup, Mail Not Sent But In Sent Folder

  • 2 replies
  • 1 has this problem
  • 24 views
  • Last reply by MIkeyLV

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Email Provider: mail.silverknight.com (via webhostinghub.com) ISP: Comcast Firewall: Windows Defender (current auto-updated version) Antivirus: Avast program=18.7.2354 / virus definitions=181107-0 (both up to date and auto updated) OS: Windows 10 Home (auto updated to current version) Thunderbird: 60.3.0 (32-bit)

Every once in a while, I get a very fast pop-up (less than a second) that says there was a send mail SMTP failure and (from what I could quickly read) that the mail was not sent. But the mail ends up in my sent mailbox. I verified as I had to send an email while on the phone with the recipient, got the popup, mail was in sent, but they never got it. I then went into sent and forwarded them that email, which they then got (Subject line difference of Re vs FW).

Any ideas?

Email Provider: mail.silverknight.com (via webhostinghub.com) ISP: Comcast Firewall: Windows Defender (current auto-updated version) Antivirus: Avast program=18.7.2354 / virus definitions=181107-0 (both up to date and auto updated) OS: Windows 10 Home (auto updated to current version) Thunderbird: 60.3.0 (32-bit) Every once in a while, I get a very fast pop-up (less than a second) that says there was a send mail SMTP failure and (from what I could quickly read) that the mail was not sent. But the mail ends up in my sent mailbox. I verified as I had to send an email while on the phone with the recipient, got the popup, mail was in sent, but they never got it. I then went into sent and forwarded them that email, which they then got (Subject line difference of Re vs FW). Any ideas?
Attached screenshots

All Replies (2)

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I would say disable mail scanning in Avast. it is somewhat unnecessary anyway.

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I'll give that a try. As it doesn't happen often, I'll report back in a week or so.