diff --git a/dlls/windows.gaming.input/main.c b/dlls/windows.gaming.input/main.c
index e97322212e4..bf6b990a623 100644
--- a/dlls/windows.gaming.input/main.c
+++ b/dlls/windows.gaming.input/main.c
@@ -117,7 +117,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_gamepad_GetTrustLevel(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_gamepad_GetAt(
-    IVectorView_Gamepad *iface, ULONG index, IGamepad **value)
+        IVectorView_Gamepad *iface, UINT32 index, IGamepad **value)
 {
     FIXME("iface %p, index %#x, value %p stub!\n", iface, index, value);
     *value = NULL;
@@ -125,7 +125,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_gamepad_GetAt(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_gamepad_get_Size(
-    IVectorView_Gamepad *iface, ULONG *value)
+        IVectorView_Gamepad *iface, UINT32 *value)
 {
     FIXME("iface %p, value %p stub!\n", iface, value);
     *value = 0;
@@ -133,7 +133,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_gamepad_get_Size(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_gamepad_IndexOf(
-    IVectorView_Gamepad *iface, IGamepad *element, ULONG *index, BOOLEAN *found)
+        IVectorView_Gamepad *iface, IGamepad *element, UINT32 *index, BOOLEAN *found)
 {
     FIXME("iface %p, element %p, index %p, found %p stub!\n", iface, element, index, found);
     *index = 0;
@@ -142,8 +142,8 @@ static HRESULT STDMETHODCALLTYPE vector_view_gamepad_IndexOf(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_gamepad_GetMany(
-        IVectorView_Gamepad *iface, ULONG start_index,
-        ULONG items_size, IGamepad **items, UINT *value)
+        IVectorView_Gamepad *iface, UINT32 start_index,
+        UINT32 items_size, IGamepad **items, UINT *value)
 {
     FIXME("iface %p, start_index %#x, items %p, value %p stub!\n", iface, start_index, items, value);
     *value = 0;
@@ -243,7 +243,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_GetTrustLevel(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_GetAt(
-    IVectorView_RawGameController *iface, ULONG index, IRawGameController **value)
+        IVectorView_RawGameController *iface, UINT32 index, IRawGameController **value)
 {
     FIXME("iface %p, index %#x, value %p stub!\n", iface, index, value);
     *value = NULL;
@@ -251,7 +251,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_GetAt(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_get_Size(
-    IVectorView_RawGameController *iface, ULONG *value)
+        IVectorView_RawGameController *iface, UINT32 *value)
 {
     FIXME("iface %p, value %p stub!\n", iface, value);
     *value = 0;
@@ -259,7 +259,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_get_Size(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_IndexOf(
-    IVectorView_RawGameController *iface, IRawGameController *element, ULONG *index, BOOLEAN *found)
+        IVectorView_RawGameController *iface, IRawGameController *element, UINT32 *index, BOOLEAN *found)
 {
     FIXME("iface %p, element %p, index %p, found %p stub!\n", iface, element, index, found);
     *index = 0;
@@ -268,8 +268,8 @@ static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_IndexOf(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_raw_game_controller_GetMany(
-        IVectorView_RawGameController *iface, ULONG start_index,
-        ULONG items_size, IRawGameController **items, UINT *value)
+        IVectorView_RawGameController *iface, UINT32 start_index,
+        UINT32 items_size, IRawGameController **items, UINT *value)
 {
     FIXME("iface %p, start_index %#x, items %p, value %p stub!\n", iface, start_index, items, value);
     *value = 0;
diff --git a/dlls/windows.gaming.input/tests/input.c b/dlls/windows.gaming.input/tests/input.c
index 6ed40186df9..6ce06de346e 100644
--- a/dlls/windows.gaming.input/tests/input.c
+++ b/dlls/windows.gaming.input/tests/input.c
@@ -115,7 +115,7 @@ static void test_Gamepad(void)
     BOOLEAN found;
     HSTRING str;
     HRESULT hr;
-    ULONG size;
+    UINT32 size;
 
     gamepad_event_handler.IEventHandler_Gamepad_iface.lpVtbl = &gamepad_event_handler_vtbl;
 
@@ -292,7 +292,7 @@ static void test_RawGameController(void)
     BOOLEAN found;
     HSTRING str;
     HRESULT hr;
-    ULONG size;
+    UINT32 size;
 
     controller_event_handler.IEventHandler_RawGameController_iface.lpVtbl = &controller_event_handler_vtbl;
 
diff --git a/dlls/windows.media.speech/main.c b/dlls/windows.media.speech/main.c
index 1a9ba51b071..c358b991be2 100644
--- a/dlls/windows.media.speech/main.c
+++ b/dlls/windows.media.speech/main.c
@@ -116,14 +116,14 @@ static HRESULT STDMETHODCALLTYPE vector_view_voice_information_GetTrustLevel(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_voice_information_GetAt(
-    IVectorView_VoiceInformation *iface, ULONG index, IVoiceInformation **value)
+        IVectorView_VoiceInformation *iface, UINT32 index, IVoiceInformation **value)
 {
     FIXME("iface %p, index %#x, value %p stub!\n", iface, index, value);
     return S_OK;
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_voice_information_get_Size(
-    IVectorView_VoiceInformation *iface, ULONG *value)
+        IVectorView_VoiceInformation *iface, UINT32 *value)
 {
     FIXME("iface %p, value %p stub!\n", iface, value);
     *value = 0;
@@ -131,7 +131,7 @@ static HRESULT STDMETHODCALLTYPE vector_view_voice_information_get_Size(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_voice_information_IndexOf(
-    IVectorView_VoiceInformation *iface, IVoiceInformation *element, ULONG *index, BOOLEAN *value)
+        IVectorView_VoiceInformation *iface, IVoiceInformation *element, UINT32 *index, BOOLEAN *value)
 {
     FIXME("iface %p, element %p, index %p, value %p stub!\n", iface, element, index, value);
     *value = FALSE;
@@ -139,8 +139,8 @@ static HRESULT STDMETHODCALLTYPE vector_view_voice_information_IndexOf(
 }
 
 static HRESULT STDMETHODCALLTYPE vector_view_voice_information_GetMany(
-        IVectorView_VoiceInformation *iface, ULONG start_index,
-        ULONG items_size, IVoiceInformation **items, UINT *value)
+        IVectorView_VoiceInformation *iface, UINT32 start_index,
+        UINT32 items_size, IVoiceInformation **items, UINT *value)
 {
     FIXME("iface %p, start_index %#x, items %p, value %p stub!\n", iface, start_index, items, value);
     *value = 0;
diff --git a/dlls/windows.media.speech/tests/speech.c b/dlls/windows.media.speech/tests/speech.c
index 30244e59612..770562e9d82 100644
--- a/dlls/windows.media.speech/tests/speech.c
+++ b/dlls/windows.media.speech/tests/speech.c
@@ -53,7 +53,7 @@ static void test_SpeechSynthesizer(void)
     IAgileObject *agile_object = NULL, *tmp_agile_object = NULL;
     HSTRING str;
     HRESULT hr;
-    ULONG size;
+    UINT32 size;
 
     hr = pRoInitialize(RO_INIT_MULTITHREADED);
     ok(hr == S_OK, "RoInitialize failed, hr %#x\n", hr);
diff --git a/include/windows.foundation.collections.idl b/include/windows.foundation.collections.idl
index 250f8b9acbe..b0b9430048b 100644
--- a/include/windows.foundation.collections.idl
+++ b/include/windows.foundation.collections.idl
@@ -101,10 +101,10 @@ cpp_quote("#endif")
             ]
             interface IVectorView<T> : IInspectable
             {
-                HRESULT GetAt([in] ULONG index, [out, retval] T *value);
-                [propget] HRESULT Size([out, retval] ULONG *value);
-                HRESULT IndexOf([in, optional] T element, [out] ULONG *index, [out, retval] BOOLEAN *value);
-                HRESULT GetMany([in] ULONG start_index, [in] ULONG items_size, [out] T *items, [out, retval] ULONG *value);
+                HRESULT GetAt([in] UINT32 index, [out, retval] T *value);
+                [propget] HRESULT Size([out, retval] UINT32 *value);
+                HRESULT IndexOf([in, optional] T element, [out] UINT32 *index, [out, retval] BOOLEAN *value);
+                HRESULT GetMany([in] UINT32 start_index, [in] UINT32 items_size, [out] T *items, [out, retval] UINT32 *value);
             }
         }
 #endif