diff --git a/redo/ui_windows.h b/redo/ui_windows.h
index 262577e4..a3ef18d8 100644
--- a/redo/ui_windows.h
+++ b/redo/ui_windows.h
@@ -26,7 +26,6 @@ struct uiWindowsMakeControlParams {
 	// ui redirects the message back and calls these functions.
 	// Store the result in *lResult and return any non-FALSE value (such as TRUE) to return the given result; return FALSE to pass the notification up to your window procedure.
 	// Note that these are only issued if they come from the uiControl itself; notifications from children of the uiControl (such as a header control) will be received normally.
-	BOOL (*onWM_COMMAND)(uiControl *c, WORD code, LRESULT *lResult);
 	BOOL (*onWM_NOTIFY)(uiControl *c, NMHDR *nm, LRESULT *lResult);
 	BOOL (*onWM_HSCROLL)(uiControl *c, WORD code, LRESULT *lResult);
 
diff --git a/redo/windows/button.c b/redo/windows/button.c
index 2cdc4532..8b57714f 100644
--- a/redo/windows/button.c
+++ b/redo/windows/button.c
@@ -33,6 +33,7 @@ static void onDestroy(void *data)
 {
 	struct button *b = (struct button *) data;
 
+	uiWindowsUnregisterWM_COMMANDHandler(b->hwnd);
 	uiFree(b);
 }
 
@@ -100,7 +101,6 @@ uiButton *uiNewButton(const char *text)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
@@ -109,6 +109,7 @@ uiButton *uiNewButton(const char *text)
 	uiFree(wtext);
 
 	b->hwnd = (HWND) uiControlHandle(uiControl(b));
+	uiWindowsRegisterWM_COMMANDHandler(b->hwnd, onWM_COMMAND, uiControl(b));
 
 	b->onClicked = defaultOnClicked;
 
diff --git a/redo/windows/checkbox.c b/redo/windows/checkbox.c
index 74f0986e..edc70c01 100644
--- a/redo/windows/checkbox.c
+++ b/redo/windows/checkbox.c
@@ -41,6 +41,7 @@ static void onDestroy(void *data)
 {
 	struct checkbox *c = (struct checkbox *) data;
 
+	uiWindowsUnregisterWM_COMMANDHandler(c->hwnd);
 	uiFree(c);
 }
 
@@ -115,7 +116,6 @@ uiCheckbox *uiNewCheckbox(const char *text)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
@@ -124,6 +124,7 @@ uiCheckbox *uiNewCheckbox(const char *text)
 	uiFree(wtext);
 
 	c->hwnd = (HWND) uiControlHandle(uiControl(c));
+	uiWindowsRegisterWM_COMMANDHandler(c->hwnd, onWM_COMMAND, uiControl(c));
 
 	c->onToggled = defaultOnToggled;
 
diff --git a/redo/windows/combobox.c b/redo/windows/combobox.c
index 8ba47453..f1b7e905 100644
--- a/redo/windows/combobox.c
+++ b/redo/windows/combobox.c
@@ -6,11 +6,6 @@ struct combobox {
 	HWND hwnd;
 };
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -68,7 +63,6 @@ uiCombobox *uiNewCombobox(void)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/container.c b/redo/windows/container.c
index 60a589c1..b443627c 100644
--- a/redo/windows/container.c
+++ b/redo/windows/container.c
@@ -58,11 +58,6 @@ void uninitContainer(void)
 		logLastError("error unregistering container window class in uninitContainer()");
 }
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -89,7 +84,6 @@ void uiMakeContainer(uiControl *c)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/control.c b/redo/windows/control.c
index 188e16d6..aa9341ac 100644
--- a/redo/windows/control.c
+++ b/redo/windows/control.c
@@ -13,7 +13,6 @@ void osSingleDestroy(void *internal)
 	struct singleHWND *s = (struct singleHWND *) internal;
 
 	(*(s->onDestroy))(s->onDestroyData);
-	uiWindowsUnregisterWM_COMMANDHandler(s->hwnd);
 	uiWindowsUnregisterWM_NOTIFYHandler(s->hwnd);
 	uiWindowsUnregisterWM_HSCROLLHandler(s->hwnd);
 	if (DestroyWindow(s->hwnd) == 0)
@@ -120,7 +119,6 @@ void uiWindowsMakeControl(uiControl *c, uiWindowsMakeControlParams *p)
 	if (s->hwnd == NULL)
 		logLastError("error creating control in uiWindowsMakeControl()");
 
-	uiWindowsRegisterWM_COMMANDHandler(s->hwnd, p->onWM_COMMAND, uiControl(c));
 	uiWindowsRegisterWM_NOTIFYHandler(s->hwnd, p->onWM_NOTIFY, uiControl(c));
 	uiWindowsRegisterWM_HSCROLLHandler(s->hwnd, p->onWM_HSCROLL, uiControl(c));
 
diff --git a/redo/windows/entry.c b/redo/windows/entry.c
index ae4c2571..68d7e7b2 100644
--- a/redo/windows/entry.c
+++ b/redo/windows/entry.c
@@ -36,6 +36,7 @@ static void onDestroy(void *data)
 {
 	struct entry *e = (struct entry *) data;
 
+	uiWindowsUnregisterWM_COMMANDHandler(e->hwnd);
 	uiFree(e);
 }
 
@@ -111,7 +112,6 @@ uiEntry *uiNewEntry(void)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
@@ -119,6 +119,7 @@ uiEntry *uiNewEntry(void)
 	uiWindowsMakeControl(uiControl(e), &p);
 
 	e->hwnd = (HWND) uiControlHandle(uiControl(e));
+	uiWindowsRegisterWM_COMMANDHandler(e->hwnd, onWM_COMMAND, uiControl(e));
 
 	e->onChanged = defaultOnChanged;
 
diff --git a/redo/windows/group.c b/redo/windows/group.c
index 4017cc70..fa5093fb 100644
--- a/redo/windows/group.c
+++ b/redo/windows/group.c
@@ -6,11 +6,6 @@ struct group {
 	HWND hwnd;
 };
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -55,7 +50,6 @@ uiGroup *uiNewGroup(const char *text)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/label.c b/redo/windows/label.c
index c9230048..9db700cf 100644
--- a/redo/windows/label.c
+++ b/redo/windows/label.c
@@ -6,11 +6,6 @@ struct label {
 	HWND hwnd;
 };
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -68,7 +63,6 @@ uiLabel *uiNewLabel(const char *text)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/progressbar.c b/redo/windows/progressbar.c
index 09b6dd1d..50a7f2e1 100644
--- a/redo/windows/progressbar.c
+++ b/redo/windows/progressbar.c
@@ -6,11 +6,6 @@ struct progressbar {
 	HWND hwnd;
 };
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -63,7 +58,6 @@ uiProgressBar *uiNewProgressBar(void)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = FALSE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/separator.c b/redo/windows/separator.c
index ea9b04c4..6c14d751 100644
--- a/redo/windows/separator.c
+++ b/redo/windows/separator.c
@@ -10,11 +10,6 @@ struct separator {
 	HWND hwnd;
 };
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -57,7 +52,6 @@ uiSeparator *uiNewHorizontalSeparator(void)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/slider.c b/redo/windows/slider.c
index f3389961..ded35e7a 100644
--- a/redo/windows/slider.c
+++ b/redo/windows/slider.c
@@ -13,11 +13,6 @@ struct slider {
 	void *onChangedData;
 };
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	return FALSE;
@@ -94,7 +89,6 @@ uiSlider *uiNewSlider(intmax_t min, intmax_t max)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
diff --git a/redo/windows/spinbox.c b/redo/windows/spinbox.c
index 2ee38a3d..5de356c0 100644
--- a/redo/windows/spinbox.c
+++ b/redo/windows/spinbox.c
@@ -61,6 +61,7 @@ static void onDestroy(void *data)
 {
 	struct spinbox *s = (struct spinbox *) data;
 
+	uiWindowsUnregisterWM_COMMANDHandler(s->hwnd);
 	uiFree(s);
 }
 
@@ -169,7 +170,6 @@ uiSpinbox *uiNewSpinbox(intmax_t min, intmax_t max)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;
@@ -177,6 +177,7 @@ uiSpinbox *uiNewSpinbox(intmax_t min, intmax_t max)
 	uiWindowsMakeControl(uiControl(s), &p);
 
 	s->hwnd = (HWND) uiControlHandle(uiControl(s));
+	uiWindowsRegisterWM_COMMANDHandler(s->hwnd, onWM_COMMAND, uiControl(s));
 
 	recreateUpDown(s);
 	s->inhibitChanged = TRUE;
diff --git a/redo/windows/tab.c b/redo/windows/tab.c
index 30cce370..999dddce 100644
--- a/redo/windows/tab.c
+++ b/redo/windows/tab.c
@@ -41,11 +41,6 @@ static void showHidePage(struct tab *t, LRESULT which, int hide)
 
 // control implementation
 
-static BOOL onWM_COMMAND(uiControl *c, WORD code, LRESULT *lResult)
-{
-	return FALSE;
-}
-
 static BOOL onWM_NOTIFY(uiControl *c, NMHDR *nm, LRESULT *lResult)
 {
 	struct tab *t = (struct tab *) c;
@@ -218,7 +213,6 @@ uiTab *uiNewTab(void)
 	p.hInstance = hInstance;
 	p.lpParam = NULL;
 	p.useStandardControlFont = TRUE;
-	p.onWM_COMMAND = onWM_COMMAND;
 	p.onWM_NOTIFY = onWM_NOTIFY;
 	p.onWM_HSCROLL = onWM_HSCROLL;
 	p.onDestroy = onDestroy;