我的邮件服务器经常出现以下问题,那位高手帮我解决.

zwjweky

我的公司的邮件是sharemail和MDaemon.sharemail作为代理转发,而MDaemon作为发送,而sharemail没有问题.而MDaemon在发送过程中,出现无法发送,在MDaemon中"未处理邮件中"显示.过后MD服务器提示以下内容:The attached message had PERMANENT fatal delivery errors!

After one or more unsuccessful delivery attempts the attached message has been removed from the mail queue on this server.  The number and frequency of delivery attempts are determined by local configuration parameters.

YOUR MESSAGE WAS NOT DELIVERED TO ONE OR MORE RECIPIENTS!

Failed address: account1@polylight.com

: Message contains [1] file attachments
意思为:附加的邮件发生“永久”的致命投递错误！

经历了一次或数次的投递失败之后，附加的邮件已从该服务器上的邮件队列中删除。
投递尝试的次数和频率
取决于本地配置参数。

该邮件无法投递到一个或多个收信人！
请问如何解决:请回复