We are seeing a lot of network traffic from some ZCO users when they try to email an oversized file. The message sits in the Drafts folder and retries constantly. Deleting the draft doesn't fix the problem. It appears to be a problem with Outlook 2007 only and we haven't been able to reproduce it with 2003.
We are on server v. 5.0.18_GA_3011.RHEL5_64.NETWORK and are seeing this behavior with the 5.0.18 ZCO. We tried downloading the 5.20 ZCO and installing that for someone who was having the problem but that didn't fix it.
The only error I can find in the logs is this (I edited the server name/domain):
2009/12/15 15:39:38 [error] 10504#0: *89259873 client intented to send too large body: 57671658 bytes, client: 10.85.103.152, server: server.domain.edu, URL: "/service/upload?fmt=raw", host: "mail.domain.edu"
repeated approximately once a minute or however often the user's client is retrying.
It looks like the connector is not taking no for an answer, or not getting no as an answer, similar to this bug:
Bug 40396 – ZCO does not handle size exceeded errors from server
or this bug:
Bug 16340 – zco continuous retry on upload failure during send
Our server doesn't seem hammered, just our network.
Is the fix for #40396 a server-side thing? Will updating to 5.20 fix it?
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[SOLVED] problem with ZCO - it keeps trying to send oversize files 
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