diff --git a/GreenshotPlugin/Core/WindowsHelper.cs b/GreenshotPlugin/Core/WindowsHelper.cs
index 8c7ec42ef..3b1108b6c 100644
--- a/GreenshotPlugin/Core/WindowsHelper.cs
+++ b/GreenshotPlugin/Core/WindowsHelper.cs
@@ -776,10 +776,10 @@ namespace GreenshotPlugin.Core  {
 		/// </summary>
 		public WindowStyleFlags WindowStyle {
 			get {
-				return (WindowStyleFlags)User32.GetWindowLongPtr(this.hWnd, (int)WindowLongIndex.GWL_STYLE);
+				return (WindowStyleFlags)User32.GetWindowLongWrapper(this.hWnd, (int)WindowLongIndex.GWL_STYLE);
 			}
 			set {
-				User32.SetWindowLongPtr(this.hWnd, (int)WindowLongIndex.GWL_STYLE, (uint)value);
+				User32.SetWindowLongWrapper(this.hWnd, (int)WindowLongIndex.GWL_STYLE, (uint)value);
 			}
 		}
 
@@ -802,10 +802,10 @@ namespace GreenshotPlugin.Core  {
 		/// </summary>
 		public ExtendedWindowStyleFlags ExtendedWindowStyle {
 			get {
-				return (ExtendedWindowStyleFlags)User32.GetWindowLongPtr(this.hWnd, (int)WindowLongIndex.GWL_EXSTYLE);
+				return (ExtendedWindowStyleFlags)User32.GetWindowLongWrapper(this.hWnd, (int)WindowLongIndex.GWL_EXSTYLE);
 			}
 			set {
-				User32.SetWindowLongPtr(this.hWnd, (int)WindowLongIndex.GWL_EXSTYLE, (uint)value);
+				User32.SetWindowLongWrapper(this.hWnd, (int)WindowLongIndex.GWL_EXSTYLE, (uint)value);
 			}
 		}
 
diff --git a/GreenshotPlugin/UnmanagedHelpers/User32.cs b/GreenshotPlugin/UnmanagedHelpers/User32.cs
index 7efb531a3..6c9019e44 100644
--- a/GreenshotPlugin/UnmanagedHelpers/User32.cs
+++ b/GreenshotPlugin/UnmanagedHelpers/User32.cs
@@ -114,11 +114,13 @@ namespace GreenshotPlugin.UnmanagedHelpers {
 		public extern static int SendMessage(IntPtr hWnd, int wMsg, IntPtr wParam, IntPtr lParam);
 		[DllImport("user32", SetLastError=true, EntryPoint = "SendMessageA")]
 		public static extern bool SendMessage(IntPtr hWnd, uint msg, int wParam, int lParam);
-		// See: http://msdn.microsoft.com/en-us/library/windows/desktop/ms633585%28v=vs.85%29.aspx
-		[DllImport("user32", EntryPoint="GetWindowLongPtr", SetLastError=true)]
+		[DllImport("user32", SetLastError = true)]
+		public extern static uint GetWindowLong(IntPtr hwnd, int index);
+		[DllImport("user32", SetLastError = true)]
 		public extern static uint GetWindowLongPtr(IntPtr hwnd, int nIndex);
-		// See: http://msdn.microsoft.com/en-us/library/windows/desktop/ms644898%28v=vs.85%29.aspx
-		[DllImport("user32", EntryPoint = "SetWindowLongPtr", SetLastError = true)]
+		[DllImport("user32", SetLastError = true)]
+		public static extern int SetWindowLong(IntPtr hWnd, int index, uint styleFlags);
+		[DllImport("user32", SetLastError = true)]
 		public static extern int SetWindowLongPtr(IntPtr hWnd, int index, uint styleFlags);
 		[DllImport("user32", SetLastError = true)]
 		public static extern IntPtr MonitorFromWindow(IntPtr hwnd, uint dwFlags);
@@ -221,6 +223,34 @@ namespace GreenshotPlugin.UnmanagedHelpers {
 		[DllImport("user32", SetLastError = true)]
 		public static extern IntPtr CreateIconIndirect(ref IconInfo icon);
 
+		/// <summary>
+		/// Wrapper for the GetWindowLong which decides if the system is 64-bit or not and calls the right one.
+		/// </summary>
+		/// <param name="hwnd"></param>
+		/// <param name="nIndex"></param>
+		/// <returns></returns>
+		public static uint GetWindowLongWrapper(IntPtr hwnd, int nIndex) {
+			if (IntPtr.Size == 8) {
+				return GetWindowLongPtr(hwnd, nIndex);
+			} else {
+				return GetWindowLong(hwnd, nIndex);
+			}
+		}
+
+		/// <summary>
+		/// Wrapper for the SetWindowLong which decides if the system is 64-bit or not and calls the right one.
+		/// </summary>
+		/// <param name="hwnd"></param>
+		/// <param name="nIndex"></param>
+		/// <param name="styleFlags"></param>
+		public static void SetWindowLongWrapper(IntPtr hwnd, int nIndex, uint styleFlags) {
+			if (IntPtr.Size == 8) {
+				SetWindowLongPtr(hwnd, nIndex, styleFlags);
+			} else {
+				SetWindowLong(hwnd, nIndex, styleFlags);
+			}
+		}
+
 		public static uint GetGuiResourcesGDICount() {
 			return GetGuiResources(Process.GetCurrentProcess().Handle, 0);
 		}