1.症状：
使用System.Net.Mail发送邮件时遇到错误: Exceeded storage allocation. The server response was: 4.3.1 message size exceeds fixed maximum message size.
2.错误log:
ERROR 2011-10-21 13:49:31,389 [36] logException [(null)] -System.Net.Mail.SmtpException: Exceeded storage allocation. The server response was: 4.3.1 Message size exceeds fixed maximum message size
at System.Net.Mail.DataStopCommand.CheckResponse(SmtpStatusCode statusCode, String serverResponse)
at System.Net.Mail.SmtpConnection.OnClose(Object sender, EventArgs args)
at System.Net.ClosableStream.Close()
at System.Net.Mail.MailWriter.Close()
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at CustomerOrder.btnSend_Click(Object sender, EventArgs e) in d:\CustomerOrder.aspx.cs:line 907
3.解决办法：
修改Limit message size to (KB)，扩大它就ok了。具体见下图：
参考:
Exceeded storage allocation. The server response was......
http://bytes.com/topic/asp-net/answers/588778-exceeded-storage-allocation-server-response