Ошибки компоновки LNK2028 и LNK2019 при использовании Windows.h

#pragma once
#include <Windows.h>
#include <WinUser.h> 
#include <ShellAPI.h>
 
    private: System::Void button1_Click(System::Object^  sender, System::EventArgs^  e) {
                 HWND Hop;
                 Hop = FindWindow(L"Калькулятор Windows", NULL);
                 PostMessage(Hop, WM_KEYDOWN, 0x31, 0);
                 Sleep(500);
                 PostMessage(Hop, WM_KEYUP, 0x31, 0);
    }
    };
}

1>  main.cpp
1>main.obj : error LNK2028: unresolved token (0A000037) "extern "C" int __stdcall PostMessageW(struct HWND__ *,unsigned int,unsigned int,long)" (?PostMessageW@@$$J216YGHPAUHWND__@@IIJ@Z) referenced in function "private: void __clrcall WinForm::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click@MyForm@WinForm@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
1>main.obj : error LNK2028: unresolved token (0A00003D) "extern "C" struct HWND__ * __stdcall FindWindowW(wchar_t const *,wchar_t const *)" (?FindWindowW@@$$J18YGPAUHWND__@@PB_W0@Z) referenced in function "private: void __clrcall WinForm::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click@MyForm@WinForm@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
1>main.obj : error LNK2019: unresolved external symbol "extern "C" struct HWND__ * __stdcall FindWindowW(wchar_t const *,wchar_t const *)" (?FindWindowW@@$$J18YGPAUHWND__@@PB_W0@Z) referenced in function "private: void __clrcall WinForm::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click@MyForm@WinForm@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
1>main.obj : error LNK2019: unresolved external symbol "extern "C" int __stdcall PostMessageW(struct HWND__ *,unsigned int,unsigned int,long)" (?PostMessageW@@$$J216YGHPAUHWND__@@IIJ@Z) referenced in function "private: void __clrcall WinForm::MyForm::button1_Click(class System::Object ^,class System::EventArgs ^)" (?button1_Click@MyForm@WinForm@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
1>D:\MSV\Project\WinForm4\Debug\WinForm4.exe : fatal error LNK1120: 4 unresolved externals

#include <windows.h>
 
void SendToCalc(void)
{
                 HWND Hop;
                 Hop = FindWindow(L"Калькулятор Windows", NULL);
                 PostMessage(Hop, WM_KEYDOWN, 0x31, 0);
                 Sleep(500);
                 PostMessage(Hop, WM_KEYUP, 0x31, 0);
}

main.cpp
1>main.obj : error LNK2028: unresolved token (0A0003BD) "extern "C" int __stdcall PostMessageW(struct HWND__ *,unsigned int,unsigned int,long)" (?PostMessageW@@$$J216YGHPAUHWND__@@IIJ@Z) referenced in function "private: void __clrcall WinForm::MyForm::SendToCalc(void)" (?SendToCalc@MyForm@WinForm@@$$FA$AAMXXZ)
1>main.obj : error LNK2028: unresolved token (0A0003DB) "extern "C" struct HWND__ * __stdcall FindWindowW(wchar_t const *,wchar_t const *)" (?FindWindowW@@$$J18YGPAUHWND__@@PB_W0@Z) referenced in function "private: void __clrcall WinForm::MyForm::SendToCalc(void)" (?SendToCalc@MyForm@WinForm@@$$FA$AAMXXZ)
1>main.obj : error LNK2019: unresolved external symbol "extern "C" struct HWND__ * __stdcall FindWindowW(wchar_t const *,wchar_t const *)" (?FindWindowW@@$$J18YGPAUHWND__@@PB_W0@Z) referenced in function "private: void __clrcall WinForm::MyForm::SendToCalc(void)" (?SendToCalc@MyForm@WinForm@@$$FA$AAMXXZ)
1>main.obj : error LNK2019: unresolved external symbol "extern "C" int __stdcall PostMessageW(struct HWND__ *,unsigned int,unsigned int,long)" (?PostMessageW@@$$J216YGHPAUHWND__@@IIJ@Z) referenced in function "private: void __clrcall WinForm::MyForm::SendToCalc(void)" (?SendToCalc@MyForm@WinForm@@$$FA$AAMXXZ)

#pragma once
 
 
 
namespace WinForm {
 
    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 MyForm
    /// </summary>
    public ref class MyForm : public System::Windows::Forms::Form
    {
    public:
        MyForm(void)
        {
            InitializeComponent();
            //
            //TODO: Add the constructor code here
            //
        }
 
    protected:
        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        ~MyForm()
        {
            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(17, 15);
            this->button1->Name = L"button1";
            this->button1->Size = System::Drawing::Size(255, 42);
            this->button1->TabIndex = 0;
            this->button1->Text = L"button1";
            this->button1->UseVisualStyleBackColor = true;
            this->button1->Click += gcnew System::EventHandler(this, &MyForm::button1_Click);
            // 
            // MyForm
            // 
            this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
            this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
            this->ClientSize = System::Drawing::Size(284, 261);
            this->Controls->Add(this->button1);
            this->Name = L"MyForm";
            this->Text = L"MyForm";
            this->Load += gcnew System::EventHandler(this, &MyForm::MyForm_Load);
            this->ResumeLayout(false);
 
        }
#pragma endregion
    private: System::Void MyForm_Load(System::Object^  sender, System::EventArgs^  e) {
                 
 
    }
    private: System::Void button1_Click(System::Object^  sender, System::EventArgs^  e) {
    
 
 
    }
    };
}

    private: System::Void button1_Click(System::Object^  sender, System::EventArgs^  e) {
                 HWND Hop;
                 Hop = FindWindow(L"Калькулятор Windows", NULL);
                 PostMessage(Hop, WM_KEYDOWN, 0x31, 0);
                 Sleep(500);
                 PostMessage(Hop, WM_KEYUP, 0x31, 0);
    }