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
    2022-07-22T20:44:04+00:00

    If these are sync issues related to your <Trash> folder

    #1 - Can you delete everything from the Trash folder by logging into the account via webmail (using a browser)? (Suggest keeping Outlook closed while you do this)

    #2 - After you've deleted everything from the Trash folder on the server side if things, rename the OST file for the emal account (with Outlook closed). When Outlook starts again, it will automatically created a new OST file and sync everything again with the server. Does that resulve the <Sync Issues> or do you get more entries in the <Sync Issues> folder

    To see the full folder path / file name for the OST file, from within Outlook, go to

    <File> --> <Account Settings> --> <Data Files> tab

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  2. Anonymous
    2022-07-22T20:57:24+00:00

    Yes, that seems to have cleared up that little sync issue. (BTW, that was for my GW account; my GMail account had no sync errors to report.)

    Outbound email still stuck, though.

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  3. Anonymous
    2022-07-22T21:06:45+00:00

    Oops. I lied. The sync issues are back (for the Google Workspace account).

    17:01:40 Synchronizer Version 16.0.15330.20056

    17:01:40 Synchronizing Mailbox '******@59plymouth.net'

    17:01:40 Synchronizing local changes in folder 'Trash'

    17:02:00 Error synchronizing message 'Fareed: We Need a Kitchen-Sink Climate Strategy'

    17:02:00                                 [800CCC0F-0-0-322]

    17:02:01 Error synchronizing message 'Howard Rudny requested to participate in The Forward Look MoPar '

    17:02:01                                 [800CCC0F-0-0-322]

    17:02:01 Error synchronizing message '"They're all still out there, ready to go."'

    17:02:01                                 [800CCC0F-0-0-322]

    17:02:01 Error synchronizing message 'Michael Jarrett requested to participate in The Forward Look MoP'

    17:02:01                                 [800CCC0F-0-0-322]

    17:02:01 Error synchronizing message 'Question has a reply: The dreaded 0x800CCC0F sending error'

    17:02:01                                 [800CCC0F-0-0-322]

    17:03:08                   252 item(s) added to offline folder

    17:03:08                   10 item(s) deleted in offline folder

    17:03:08 Error synchronizing folder

    17:03:08                                 [800CCC0F-0-0-560]

    17:03:08 Done

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  4. Anonymous
    2022-07-22T21:07:32+00:00

    OK - so what we have is "sending an email message stays stuck in the Outbox" - that sum it up correctly?

    #1 - Does this happen on any and every message you try and send out?

    #2 - Is there anything that these messages have in common? (i.e. an elaborate signature line, attachment, recipients etc)

    #3 - Do you use any 3rd party Outlook anti-virus / anti-spam addins?

    To clean this up and trying to isolate things

    #3 - Set Outlook to <Work Offline>

    • to do that, click on the Send/Receive tab and click on the <Work Offline> (only once). This is an on/off toggle button and will turn gray when you're offline

    #3 - Close and restart Outlook

    #4 - Delete everything from the <Outbox>

    #5 - Return Outlook to work online. Not necessary but just to start things clean, close and reopen Outlook

    #6 - Does this happen when you send a simple message to someone, no attachments, no signature etc - just a benign message

    Still have the same problem?

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  5. Anonymous
    2022-07-22T21:15:38+00:00

    >>

    Oops. I lied. The sync issues are back (for the Google Workspace account).

    <<

    What is the server timeout set to? - it's on the <Advanced Tab> when looking at the email account properties via CTRL+ALT+S as described before

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