Accessing Comcast Email via MSFT Outlook or Apple Email host on Verizon WiFi or Wired Network

Sorry for the delayed response.   On Outlook, I get a "send/receive error" message and the email gets hung in the Outbox.    The specific outlook error is:

"Task 'XXXX@comcast.net - Sending' reported error (0x800CCC0F) : 'The connection to the server was interrupted. If this problem continues, contact your server administrator or Internet service provider (ISP).'"

Through trial and error, the problem is sending emails from a Comcast email address while on a Verizon / Fios wifi or hard wired network using Outlook or the Apple email ap.   If i'm on the same network, i can log into the "clunky" Comcast email system via browser / xfinity website and send / receive emails.  Also can SEND comcast emails from all non-Verizon / Fios wifi / wired networks.  That said, i can always RECEIVE all comcast emails on my Outlook / Apple email ap in real time on the same networks.  

So, the issue seems to be how the Comcast email servers interact with the Fios network.    At low traffic times of the day (e.g., 2am and over the weekend), I can send Comcast emails from Outlook or Apple Email ap periodically -- it's unstable, but emails will get out from time to time.     I'm not a system engineer or email expert, but it seems like there is something with the handoff between the Comcast servers and the Fios / Verizon network.  I'm wondering if i can use different settings on my Outlook or the Fios network to address the issue

Thanks

This is quite a detailed analysis, and we certainly appreciate all the work you've put in already looking into this. One thing we will suggest is to double-check all email settings for the third party servers. We don't have specific settings going out to each ISP other than the handshake between networks as the data is moving along. 

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