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TB does not accept the presented gmail certificate. Is this a Man in the Middle Attack?

  • 3 replies
  • 1 has this problem
  • 5 views
  • Last reply by Akemwave

Akemwave
Akemwave
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When I send a message using my Gmail account I get this error message:

"Sending of the message failed. The message could not be sent using Outgoing server (SMTP) imap.gmail.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again."

As I recall at first it was an intermittent problem. Now it happens every time. I assume sending email is not encrypted when I set this to a one time only exception rather than permanent. As I do not know it is not a Man In the Middle attack, I did not set it to accept the certificate in the future, doing one exception each time I send. I have two questions. How can I tell if it is an attack? If it is not, what must I change so that sending connections are encrypted? Thank you.

Thunderbird is version 38.30. OS is Ubuntu 14.04 LTS. See attached screen shots.

When I send a message using my Gmail account I get this error message: ***** "Sending of the message failed. The message could not be sent using Outgoing server (SMTP) imap.gmail.com for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again." ***** As I recall at first it was an intermittent problem. Now it happens every time. I assume sending email is not encrypted when I set this to a one time only exception rather than permanent. As I do not know it is not a Man In the Middle attack, I did not set it to accept the certificate in the future, doing one exception each time I send. I have two questions. How can I tell if it is an attack? If it is not, what must I change so that sending connections are encrypted? Thank you. ***** Thunderbird is version 38.30. OS is Ubuntu 14.04 LTS. See attached screen shots.
Attached screenshots

All Replies (3)

christ1
christ1
  • Top 25 Contributor
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The message could not be sent using Outgoing server (SMTP) imap.gmail.com

Outgoing server is smtp.gmail.com. Incoming server is imap.gmail.com. Verify your account settings.

Akemwave
Akemwave Question owner
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I changed the server name to smtp.gmail.com. Now I send a test message to my other address on my other mail server (home owned) it shows in my inbox on the Gmail account, on the Sent box on the Gmail account, and on the alternate email address account.


Editing outgoing servers can be found by -> Left hand window -> Local Folders -> go to bottom of window (if resolution so requires) -> Outgoing Server -> Select Server -> Click on Edit

I edited IMAP to SMTP (I get 64.233.188.108 on ping, different IP than IMAP 64.233.189.108).

I'll check it out later. Post more.

Akemwave
Akemwave Question owner
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I think after changing from sending via imap.gmail.com to smtp.gmail.com requires changing settings for copies and folders and synchronization. I will post what works properly after and if I get it to work.