The dreaded 0x800CCC0F sending error

Anonymous
2022-07-21T19:36:33+00:00

I am now running Microsoft® Outlook® 2016 MSO (Version 2206 Build 16.0.15330.20260) 64-bit, on Windows 8.1; I had been running the 32-bit version, but I upgraded to 64-bit in an attempt to resolve this error on sending: "Task '[email account] - Sending' reported error (0x800CCC0F): 'The connection to the server was interrupted....' "

My Outlook is configured for two IMAP accounts, both with Google - one is a GMail account, the other is Google Workspace account that services email for my domain (59plymouth.net). Outlook is also configured for a work Exchange account.

A few weeks ago - not sure, but I think after a reboot, and when Windows updates were applied - both IMAP accounts stopped sending. The Exchange account continues to work without issue.

The updates were July updates - 5015874, 50156268, and 50154633. Suspecting these, I backed them out and disabled updates. No luck. I then did the Outlook 64-bit upgrade. NADA.

I'd suspect Google, but my iPhone continues to work without issue for both accounts; so does my iPad (which also talks to my Exchange account).

I'm not sure where to go from here. And ideas about how to further diagnose?

adTHANKSvance,

Dan

Outlook | Windows | Classic Outlook for Windows | For business

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  1. Anonymous
    2022-08-04T20:58:14+00:00

    Well, nothing is going outbound at the moment (I continue to receive emails into the account); no sense in trying more or less attachments. I did extend the connection time to three minutes, but before that time is up, I get the 'The connection to the server was interrupted. If this problem continues, contact your server administrator or Internet service provider (ISP)' message. However, last time I was on the horn with Google, they suggested I should contact Microsoft, deeming it a problem with Outlook.

    And so it goes. It seems to me: There ought to be some diagnostic tool, that see what is or isn't going out of Outlook, and what is or isn't coming back from Google; and if something does come back, what it is unhappy about besides "the connection was interrupted".

    I am at a total loss here. I've been able to manage 20+ years of email, archived to .pst, with Outlook; and now the whole system I've set up is broken. Even after buying a new computer, and moving my Office license to it. And I just don't know why, nor does it appear I will ever know.

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  2. Karl Timmermans 3,685 Reputation points Volunteer Moderator
    2022-08-04T04:22:42+00:00

    Hi Karl, to quickly reply before heading to bed (after midnight ET) - I'll experiment in the a.m. with fewer attachments. But just to point out, this is an out-of-the-box Lenovo Windows 10 computer, followed by the free Windows 11 upgrade. I haven't installed Symantec Endpoint, or tinkered with Defender in any way.

    Then the only thing left to play with is the server timeout setting - really don't know what else to suggest given that this is a vanilla system other then trying to connect to Google support to see if they have any words of wisdom to share.

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  3. Anonymous
    2022-08-04T04:10:40+00:00

    Hi Karl, to quickly reply before heading to bed (after midnight ET) - I'll experiment in the a.m. with fewer attachments. But just to point out, this is an out-of-the-box Lenovo Windows 10 computer, followed by the free Windows 11 upgrade. I haven't installed Symantec Endpoint, or tinkered with Defender in any way.

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  4. Karl Timmermans 3,685 Reputation points Volunteer Moderator
    2022-08-04T03:58:11+00:00

    I followed this with my own test email to the same account, with only "test" in the subject line, and the body. It was successful. I then attempted to send an email with three attachments (a Word doc and two spreads, all fairly small), and I got the dreaded 0x800CCC0F sending error. This, following a login into gmail, and a clearing of the trash folder.

    Well, we know 2 things from your description, -the account is correctly configured and is working for send/receive

    That leaves only one thing - something is interfering with Outlook

    Most common cause for this kind of scenario is an anti-virus taking longer to do its thing then what Outlook has as per its server timeout setting for the account

    Quick test

    #1 - If you send a test message with only 1 attachment - does it work? If no, if you try with one of the other attachments - same result? (i.e. if the first was a Word doc - use an Excel file)

    #2 - If it works with one, does it work 2 etc?

    If Endpoint is installed on Win11, and things aren't working, would suggest uninstalling Endpoint completely for the time being, reboot the machine. repairing Office and trying the tests again

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  5. Anonymous
    2022-08-04T03:21:15+00:00

    OK, I'm back.

    I've got a new computer, running Windows 11. I've installed Office 2016 Pro Plus on it - which, according to this article, natively supports 2SV without requiring an App PW (if not a volume 2016 license, and mine is not). I've got 2SV enabled on Google, and I deleted my profile in Outlook and created a new one, configuring my work Exchange account in the process. I then attempted to add my Google Workspace Account to the profile; it successfully sent an automated test email. I followed this with my own test email to the same account, with only "test" in the subject line, and the body. It was successful. I then attempted to send an email with three attachments (a Word doc and two spreads, all fairly small), and I got the dreaded 0x800CCC0F sending error. This, following a login into gmail, and a clearing of the trash folder.

    Outlook used to work so reliably; I'm sorta at my wits end here. What can be done, to diagnose who's not happy with what? My assumption is that the systems I'm working with are deterministic 8^\

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