asp.net使用短信猫发送短信失败

Question

[STAThread]
[DllImport("sms.dll", EntryPoint = "Sms_Connection")]
public static extern uint Sms_Connection(string CopyRight, uint Com_Port, uint Com_BaudRate, out string Mobile_Type, out string CopyRightToCOM);
[DllImport("sms.dll", EntryPoint = "Sms_Disconnection")]
public static extern uint Sms_Disconnection();
[DllImport("sms.dll", EntryPoint = "Sms_Send")]
public static extern uint Sms_Send(string Sms_TelNum, string Sms_Text);
[DllImport("sms.dll", EntryPoint = "Sms_Receive")]
public static extern uint Sms_Receive(string Sms_Type, out string Sms_Text);
[DllImport("sms.dll", EntryPoint = "Sms_Delete")]
public static extern uint Sms_Delete(string Sms_Index);
[DllImport("sms.dll", EntryPoint = "Sms_AutoFlag")]
public static extern uint Sms_AutoFlag();
[DllImport("sms.dll", EntryPoint = "Sms_NewFlag")]
public static extern uint Sms_NewFlag();

运行后提示：无法加载 DLL“sms.dll”: 找不到指定的模块。
然后将sms.dll文件放在了bin目录下和release和debug中，以及system32目录中,程序干脆启动不起来，请问这该怎么解决，就想实现在asp.net页面中点击发送按钮，短信内容和手机号写死，写死的指定手机号就能收到短信，实现起来就遇到了这个问题，请大神指点。

Answer 1

64位系统，将dll放在syswow64而不是system32下，程序编译的时候点项目属性，目标选择x86，强制编译为32bit
检查你的串口本身连接是否良好