diff --git a/Greenshot/Forms/MainForm.cs b/Greenshot/Forms/MainForm.cs
index e95546a7e..9127b3462 100644
--- a/Greenshot/Forms/MainForm.cs
+++ b/Greenshot/Forms/MainForm.cs
@@ -407,10 +407,10 @@ namespace Greenshot {
 		
 		private void RegisterHotkeys() {
 			bool suc = true;
-			suc &= HotkeyHelper.RegisterHotKey((int)this.Handle, (int)HotkeyHelper.Modifiers.NONE, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureRegion));
-			suc &= HotkeyHelper.RegisterHotKey((int)this.Handle, (int)HotkeyHelper.Modifiers.ALT, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureWindow));
-			suc &= HotkeyHelper.RegisterHotKey((int)this.Handle, (int)HotkeyHelper.Modifiers.CTRL, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureFullScreen));
-			suc &= HotkeyHelper.RegisterHotKey((int)this.Handle, (int)HotkeyHelper.Modifiers.SHIFT, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureLastRegion));
+			suc &= HotkeyHelper.RegisterHotKey(this.Handle, (uint)HotkeyHelper.Modifiers.NONE, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureRegion));
+			suc &= HotkeyHelper.RegisterHotKey(this.Handle, (uint)HotkeyHelper.Modifiers.ALT, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureWindow));
+			suc &= HotkeyHelper.RegisterHotKey(this.Handle, (uint)HotkeyHelper.Modifiers.CTRL, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureFullScreen));
+			suc &= HotkeyHelper.RegisterHotKey(this.Handle, (uint)HotkeyHelper.Modifiers.SHIFT, HotkeyHelper.VK_SNAPSHOT, new HotKeyHandler(CaptureLastRegion));
 			if (!suc) {
 				MessageBox.Show(lang.GetString(LangKey.warning_hotkeys),lang.GetString(LangKey.warning));
 			}
@@ -644,7 +644,7 @@ namespace Greenshot {
 			LOG.Info("Exit: " + EnvironmentInfo.EnvironmentToString(false));
 			try {
 				// Make sure hotkeys are disabled
-				HotkeyHelper.UnregisterHotkeys(Handle.ToInt32());
+				HotkeyHelper.UnregisterHotkeys(Handle);
 			} catch (Exception e) {
 				LOG.Error("Error unregistering hotkeys!", e);
 			}
diff --git a/GreenshotCore/Helpers/HotkeyHelper.cs b/GreenshotCore/Helpers/HotkeyHelper.cs
index ae9a053ab..10167d168 100644
--- a/GreenshotCore/Helpers/HotkeyHelper.cs
+++ b/GreenshotCore/Helpers/HotkeyHelper.cs
@@ -32,11 +32,11 @@ namespace Greenshot.Helpers {
 	public class HotkeyHelper {
 		private static log4net.ILog LOG = log4net.LogManager.GetLogger(typeof(HotkeyHelper));
 		
-		private const int WM_HOTKEY = 0x312;
-		public const int VK_SNAPSHOT = 0x2C;
+		private const uint WM_HOTKEY = 0x312;
+		public const uint VK_SNAPSHOT = 0x2C;
 		
 		#region enums
-		public enum Modifiers : int {
+		public enum Modifiers : uint {
 			NONE = 0,
 			ALT = 1,
 			CTRL = 2,
@@ -53,14 +53,25 @@ namespace Greenshot.Helpers {
 		}
 
 		#region User32
-		[DllImport("user32.dll")]
-		private static extern bool RegisterHotKey (int hwnd, int id, int fsModifiers, int vk);
-		[DllImport("user32.dll")]
-		private static extern bool UnregisterHotKey (int hwnd, int id);
+		[DllImport("user32.dll", SetLastError = true)]
+		[return: MarshalAs(UnmanagedType.Bool)]
+		private static extern bool RegisterHotKey(IntPtr hWnd, int id, uint fsModifiers, uint virtualKeyCode);
+
+		[DllImport("user32.dll", SetLastError = true)]
+		[return: MarshalAs(UnmanagedType.Bool)]
+		private static extern bool UnregisterHotKey(IntPtr hWnd, int id);
 		#endregion
 		
-		public static bool RegisterHotKey(int hnd, int modifierKeyCode, int virtualKeyCode, HotKeyHandler handler) {
-			if (RegisterHotKey(hnd, hotKeyCounter, modifierKeyCode, virtualKeyCode)) {
+		/// <summary>
+		/// Register a hotkey
+		/// </summary>
+		/// <param name="hWnd">The window which will get the event</param>
+		/// <param name="modifierKeyCode">The modifier, e.g.: Modifiers.CTRL, Modifiers.NONE or Modifiers.ALT</param>
+		/// <param name="virtualKeyCode">The virtual key code</param>
+		/// <param name="handler">A HotKeyHandler, this will be called to handle the hotkey press</param>
+		/// <returns></returns>
+		public static bool RegisterHotKey(IntPtr hWnd, uint modifierKeyCode, uint virtualKeyCode, HotKeyHandler handler) {
+			if (RegisterHotKey(hWnd, hotKeyCounter, modifierKeyCode, virtualKeyCode)) {
 				keyHandlers.Add(hotKeyCounter, handler);
 				hotKeyCounter++;
 				return true;
@@ -70,9 +81,9 @@ namespace Greenshot.Helpers {
 			}
 		}
 		
-		public static void UnregisterHotkeys(int hnd) {
+		public static void UnregisterHotkeys(IntPtr hWnd) {
 			foreach(int hotkey in keyHandlers.Keys) {
-				UnregisterHotKey(hnd, hotkey);
+				UnregisterHotKey(hWnd, hotkey);
 			}
 			// Remove all key handlers
 			keyHandlers.Clear();