这是HTML或RTF消息吗？

So is this HTML or RTF message?

这是针对Exchange存储的吗？

Is this against an Exchange store?

有可能打开太多对象并超过RPC通道限制。

Chances are you are opening too many objects and go over the RPC channel limit.

不要使用多点符号（例如mailItem 。 附件 [ lIndex ]相当于
mailItem 。 Attachments.Item（ lIndex）或
mailItem 。 附件 。 添加）并在您不在时释放所有COM对象使用Marshal.ReleaseComObject（）将它们放在循环中。

Do not use multiple dot notation (such as mailItem.Attachments[lIndex] which is equivalent to mailItem.Attachments.Item(lIndex) or mailItem.Attachments.Add) and release all COM objects as soon as you are done with them in the loop using Marshal.ReleaseComObject().