PlaySound Link error

This program is suppose to play a sound when a button is pressesd:

The following error has accured during my build:

------ Build started: Project: PlaySoundWave, Configuration: Debug
Win32 ------
Linking...
PlaySoundWave.obj : error LNK2028: unresolved token (0A00000E) "extern
"C" int __stdcall sndPlaySoundW(wchar_t const *,unsigned int)"
(?sndPlaySoundW@@$$J18YGHPB_WI@Z) referenced in function "private: void
__clrcall PlaySoundWave::Form1::button1_Click(class System::Object
^,class System::EventArgs ^)"
(?button1_Click@Form1@PlaySoundWave@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
PlaySoundWave.obj : error LNK2019: unresolved external symbol "extern
"C" int __stdcall sndPlaySoundW(wchar_t const *,unsigned int)"
(?sndPlaySoundW@@$$J18YGHPB_WI@Z) referenced in function "private: void
__clrcall PlaySoundWave::Form1::button1_Click(class System::Object
^,class System::EventArgs ^)"
(?button1_Click@Form1@PlaySoundWave@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
C:\Documents and Settings\Administrator\My Documents\Visual Studio
2005\Projects\PlaySoundWave\Debug\PlaySoundWave.exe : fatal error
LNK1120: 2 unresolved externals
Build log was saved at "file://c:\Documents and
Settings\Administrator\My Documents\Visual Studio
2005\Projects\PlaySoundWave\PlaySoundWave\Debug\BuildLog.htm"
PlaySoundWave - 3 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped
==========

Here is the code for the class:

#pragma once
#include <windows.h> // for PlaySound()
#include <Mmsystem.h>

namespace PlaySoundWave {

    using namespace System;
    using namespace System::ComponentModel;
    using namespace System::Collections;
    using namespace System::Windows::Forms;
    using namespace System::Data;
    using namespace System::Drawing;

    /// <summary>
    /// Summary for Form1
    ///
    /// WARNING: If you change the name of this class, you will need to
change the
    /// 'Resource File Name' property for the managed resource
compiler tool
    /// associated with all .resx files this class depends on.
Otherwise,
    /// the designers will not be able to interact properly with
localized
    /// resources associated with this form.
    /// </summary>
    public ref class Form1 : public System::Windows::Forms::Form
    {
    public:
        Form1(void)
        {
            InitializeComponent();
            //
            //TODO: Add the constructor code here
            //
        }

    protected:
        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        ~Form1()
        {
            if (components)
            {
                delete components;
            }
        }
    private: System::Windows::Forms::Button^ button1;
    protected:

    private:
        /// <summary>
        /// Required designer variable.
        /// </summary>
        System::ComponentModel::Container ^components;

#pragma region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        void InitializeComponent(void)
        {
            this->button1 = (gcnew System::Windows::Forms::Button());
            this->SuspendLayout();
            //
            // button1
            //
            this->button1->Location = System::Drawing::Point(210, 175);
            this->button1->Name = L"button1";
            this->button1->Size = System::Drawing::Size(75, 23);
            this->button1->TabIndex = 0;
            this->button1->Text = L"button1";
            this->button1->UseVisualStyleBackColor = true;
            this->button1->Click += gcnew System::EventHandler(this,
&Form1::button1_Click);
            //
            // Form1
            //
            this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
            this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
            this->ClientSize = System::Drawing::Size(292, 266);
            this->Controls->Add(this->button1);
            this->Name = L"Form1";
            this->Text = L"Form1";
            this->ResumeLayout(false);

        }
#pragma endregion
    private: System::Void button1_Click(System::Object^ sender,
System::EventArgs^ e) {
                    LPCWSTR filename = L"start.wav";

sndPlaySound(filename,SND_LOOP);//NULL,SND_FILENAME|SND_LOOP|SND_ASYNC);

             }
    };
}

Does anyone know what the problem is? I thought it is a linking
problem. I have included Coredll.lib in the project general linker
additional library directories.

What could it be?

THX