先打开邮件,从右边的Drop down里选Show Original就可以看到完整的Header
Received: from [xxx.xxx.xxx.xxx] by webxxxx.mail.spx.yahoo.com via HTTP; Sat, 03 Apr 2010 06:23:56 PDT
X-Mailer: YahooMailClassic/10.0.8 YahooMailWebService/0.8.100.260964
Date: Sat, 3 Apr 2010 06:23:56 -0700 (PDT)
[xxx.xxx.xxx.xxx]就是发件人的IP Address。你可以先给自己发几个email验证一下