This is happening when we try to send an email generated by a custom app (customer lead sheet), but only on 1 machine. I have updated to all the most recent patches as of June 2nd 2010, and tried manually setting the NIC to 100mbps full and half duplex.
OS is Windows XP Sp3, app is located on a Windows Server Standard 2008 shared volume.
The proccess is -
1 - Lead sheet is created; 2 - Document is printed to PDF format then attached to an email (usually to the Sales Rep for that region); 3 - SMTP engine connects to external mail gateway and attempts to send, this is when the socket error occurs.
Process then appears to end noramlly (no memory leaks etc).
Interesting thing, we have an option in the tools menu to "test email connection". This will work over and over again, but only if it is done BEFORE the socket error occurs. After the error the test connection throws the same socket error.
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