当你将邮件内容发送完成后,再发送一个"\r\n.\r\n";
在FoxMail和OutLook Express中我都试过,没有问题.
我也在搞这个东西.
我也有一个问题不知楼主是否能帮我解决:邮件服务器如何与别的邮件服务器交换邮件?比如说用"xyz@112.com"发送到"abc@223.com" ,112.com上的邮件服务器如何将本地的这封邮件发送到223.com上的邮件服务器?(可不要建议到223.com上去申请一个免费邮箱)
这个问题我想你早晚也会遇到,如果已经(或以后)解决请告诉我如何解决(xhzxlqt@163.com,xhzxlqt@126.com)
谢谢!

“当你将邮件内容发送完成后,再发送一个"\r\n.\r\n";在FoxMail和OutLook Express中我都试过,没有问题”

你说的方法我试过了，在FoxMail中可以通过，但不知为何，OutLook Express一直在等待接收数据，而不结束，很奇怪的？

我昨晚就在想这个问题，我想应该可以通过自身的SMTP服务器发到另外的服务器上，如果解决了，给你email！

你说的问题我最初也遇到过,已经解决,现将POP3的代码贴上来:
if(rectxt.SubString(1,4).UpperCase()=="RETR")
          {
            if(ipop3status<2)
            {
             sendtxt="-ERR authentication required.\r\n";
             try
             {
               pStream->WriteBuffer(sendtxt.c_str(),sendtxt.Length());
             }
             catch(...)
             {
               Terminate();
             }
            }
            else
            {
            sPara=rectxt.SubString(6,rectxt.Length()-7);
            int no=StrToInt(sPara)-iDeleted;
            TSearchRec sr;
            int iAttributes = 0;
            iAttributes |= faAnyFile;
            int messagenumber=0;
            long messagebyte=0;

             FILE *popfp;

                int lfilelen,ifread;
                AnsiString str,str1;
            if (FindFirst(mailpath+Domain+"\\"+Name+"\\*.mal", iAttributes, sr) == 0)
             {
              do
              {
               if (sr.Name.SubString(1,1)!=".")
               {
                 messagenumber++;
                if(messagenumber==no)
                {
                int ifilesize=sr.Size;
                sPOPFilename=mailpath+Domain+"\\"+Name+"\\"+sr.Name;
                popfp=fopen((mailpath+Domain+"\\"+Name+"\\"+sr.Name).c_str(),"rt");
                if(popfp)
                {
                sendtxt="+OK "+IntToStr(sr.Size)+" octets\r\n";
                     try
                     {
                       pStream->WriteBuffer(sendtxt.c_str(),sendtxt.Length());
                     }
                     catch(...)
                     {
                     Terminate();
                     }
//                 while(!feof(popfp))
                 while(ifilesize)
                {
                 // fgets(ch,513,popfp);
                 char ch[513];
                 ZeroMemory(ch,513);
                 if(ifilesize<=513)
                 {
                  fread((char*)ch,ifilesize,1,popfp);
                  str=AnsiString(ch).SubString(1,ifilesize);
                  ifilesize=0;
                 }
                 if(ifilesize>513)
                 {
                  fread((char*)ch,513,1,popfp);
                  str=AnsiString(ch).SubString(1,513);
                  ifilesize-=513;
                 }

                  str1=str;

                  if((str.SubString(str.Length()-1,1)=="=")&&(str.SubString(str.Length()-2,1)!="?"))
                  {
                   str1=str.SubString(1,str.Length()-2);
                  }
                  sendtxt=str1;
                     try
                     {
                       pStream->WriteBuffer(sendtxt.c_str(),sendtxt.Length());
                     }
                     catch(...)
                     {
                     Terminate();
                     }
                }
                  sendtxt="\r\n.\r\n";
                     try
                     {
                       pStream->WriteBuffer(sendtxt.c_str(),sendtxt.Length());
                     }
                     catch(...)
                     {
                        Terminate();
                     }
                if(popfp)
                fclose(popfp);
                break;
                }
               }
              }
              } while (FindNext(sr) == 0);
               FindClose(sr);
             }
             }
            }