我用C#写的桌面程序为什么一运行就报错“尝试读取或写入受保护的内存。这通常指示其他内存已损坏。"

我打开的窗口只是执行了数据库查询，然后放到数据窗口中显示啊，没有其他功能。求教各位老师这是什么原因？
处理 System.AccessViolationException
  Message="尝试读取或写入受保护的内存。这通常指示其他内存已损坏。"
  Source="System.Drawing"
  StackTrace:
       在 System.Drawing.SafeNativeMethods.Gdip.GdipDrawRectangleI(HandleRef graphics, HandleRef pen, Int32 x, Int32 y, Int32 width, Int32 height)
       在 System.Drawing.Graphics.DrawRectangle(Pen pen, Int32 x, Int32 y, Int32 width, Int32 height)
       在 System.Drawing.Graphics.DrawRectangle(Pen pen, Rectangle rect)
       在 System.Windows.Forms.DataGridView.PaintBorder(Graphics g, Rectangle clipRect, Rectangle bounds)
       在 System.Windows.Forms.DataGridView.OnPaint(PaintEventArgs e)
       在 System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer, Boolean disposeEventArgs)
       在 System.Windows.Forms.Control.WmPaint(Message& m)
       在 System.Windows.Forms.Control.WndProc(Message& m)
       在 System.Windows.Forms.DataGridView.WndProc(Message& m)
       在 System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       在 System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       在 System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       在 System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       在 System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
       在 System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       在 System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       在 System.Windows.Forms.Application.Run(Form mainForm)
       在 WindowsApplication1.Program.Main() 位置 D:\我的文档\Visual Studio 2005\Projects\WindowsApplication4\WindowsApplication4\Program.cs:行号 17
       在 System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args)
       在 System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       在 Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       在 System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       在 System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       在 System.Threading.ThreadHelper.ThreadStart()
有关调用实时(JIT)调试而不是此对话框的详细信息，
请参见此消息的结尾。************** 异常文本 **************
System.InvalidOperationException: 对象当前正在其他地方使用。
   在 System.Drawing.Graphics.CheckErrorStatus(Int32 status)
   在 System.Drawing.Graphics.FillPolygon(Brush brush, Point[] points, FillMode fillMode)
   在 System.Drawing.Graphics.FillPolygon(Brush brush, Point[] points)
   在 System.Windows.Forms.ComboBox.FlatComboAdapter.DrawFlatComboDropDown(ComboBox comboBox, Graphics g, Rectangle dropDownRect)
   在 System.Windows.Forms.ToolStripComboBox.ToolStripComboBoxControl.ToolStripComboBoxFlatComboAdapter.DrawFlatComboDropDown(ComboBox comboBox, Graphics g, Rectangle dropDownRect)
   在 System.Windows.Forms.ComboBox.FlatComboAdapter.DrawFlatCombo(ComboBox comboBox, Graphics g)
   在 System.Windows.Forms.ComboBox.WndProc(Message& m)
   在 System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   在 System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   在 System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
************** 已加载的程序集 **************
mscorlib
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/Microsoft.NET/Framework/v2.0.50727/mscorlib.dll
----------------------------------------
QuickStoresToolbar
    程序集版本: 1.1.0.0
    Win32 版本: 1.1.0.0
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/QuickStoresToolbar/1.1.0.0__318d21d4b0463a3b/QuickStoresToolbar.dll
----------------------------------------
System.Windows.Forms
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System.Windows.Forms/2.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System/2.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Drawing
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System.Drawing/2.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
Update
    程序集版本: 1.1.3.0
    Win32 版本: 1.0.0.0
    基本代码: file:///C:/WINDOWS/assembly/GAC_32/Update/1.1.3.0__318d21d4b0463a3b/Update.exe
----------------------------------------
Interop.SHDocVw
    程序集版本: 1.1.0.0
    Win32 版本: 1.1.0.0
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/Interop.SHDocVw/1.1.0.0__ffdc4657f9a00288/Interop.SHDocVw.dll
----------------------------------------
Microsoft.VisualBasic
    程序集版本: 8.0.0.0
    Win32 版本: 8.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/Microsoft.VisualBasic/8.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualBasic.dll
----------------------------------------
System.Configuration
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System.Configuration/2.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Xml
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System.Xml/2.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
mscorlib.resources
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/Microsoft.NET/Framework/v2.0.50727/mscorlib.dll
----------------------------------------
System.Windows.Forms.resources
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System.Windows.Forms.resources/2.0.0.0_zh-CHS_b77a5c561934e089/System.Windows.Forms.resources.dll
----------------------------------------
System.Drawing.resources
    程序集版本: 2.0.0.0
    Win32 版本: 2.0.50727.42 (RTM.050727-4200)
    基本代码: file:///C:/WINDOWS/assembly/GAC_MSIL/System.Drawing.resources/2.0.0.0_zh-CHS_b03f5f7f11d50a3a/System.Drawing.resources.dll
----------------------------------------************** JIT 调试 **************
要启用实时(JIT)调试，
该应用程序或计算机的 .config 文件(machine.config)的 system.windows.forms 节中必须设置
jitDebugging 值。
编译应用程序时还必须启用
调试。例如: <configuration>
    <system.windows.forms jitDebugging="true" />
</configuration>启用 JIT 调试后，任何无法处理的异常
都将被发送到在此计算机上注册的 JIT 调试器，
而不是由此对话框处理。