The message reported by the connector and the message you've shown in the server logs may or may not be correlated, and my hunch is they aren't.
The connector is reporting the upload of the message to send failed because it was too large while the server log snippet shows a SOAP request indicating the auth token has expired. The reason I think they aren't correlated is that the send from ZCO uses does a file upload which isn't a SOAP request.
To get the root cause, enable ZCO logging with HTTP tracing (using ZCOLogCtl.exe) on one of the client machines and reproduce the behavior. Inspect the logs and search for the file upload fault. I'm guessing you'll see that the user tried to send a message and the server rejected the upload because the message is too large. |