diff --git a/source/dll/draw.c b/source/dll/draw.c
index 8b74783..235ed14 100644
--- a/source/dll/draw.c
+++ b/source/dll/draw.c
@@ -407,6 +407,12 @@ void DrawClock(HWND hwnd, HDC hdc, const SYSTEMTIME* pt)
 	GetClientRect(hwnd, &rcClock);
 	wclock = rcClock.right;
 	hclock = rcClock.bottom;
+	if(g_bTaskbarPosChanging)
+	{
+		g_OrigClockWidth = wclock;
+		g_OrigClockHeight = hclock;
+		g_bTaskbarPosChanging = FALSE;
+	}
 	
 	size = (DWORD)CalcRect(hwnd, &wtext, &htext);
 	if(wclock < LOWORD(size) || hclock < HIWORD(size))
diff --git a/source/dll/main2.c b/source/dll/main2.c
index 02043c3..53b2c29 100644
--- a/source/dll/main2.c
+++ b/source/dll/main2.c
@@ -20,6 +20,8 @@ BOOL    g_bVisualStyle;        // Windows XP theme is used
 BOOL    g_bNoClock;            // don't customize clock
 int     g_OrigClockWidth;      // original clock width
 int     g_OrigClockHeight;     // original clock height
+RECT    g_rcTaskbar;
+BOOL    g_bTaskbarPosChanging;
 BOOL    g_bLMousePassThru;     // pass through left button messages
 
 #define SUBCLASS_ID			1
@@ -66,6 +68,9 @@ void InitClock(HWND hwnd)
 	GetWindowRect(hwnd, &rc);
 	g_OrigClockWidth = rc.right - rc.left;
 	g_OrigClockHeight = rc.bottom - rc.top;
+	// Save taskbar position
+	GetWindowRect(GetParent(GetParent(hwnd)), &g_rcTaskbar);
+	g_bTaskbarPosChanging = FALSE;
 	
 	// tell tclock.exe clock's HWND
 	PostMessage(g_hwndTClockMain, TCM_HWNDCLOCK, 0, (LPARAM)hwnd);
@@ -77,8 +82,11 @@ void InitClock(HWND hwnd)
 	InitUserStr();     // userstr.c
 	
 	// subclassfy the clock window !!
-	SetWindowSubclass(GetParent(hwnd), SubclassTrayProc, SUBCLASSTRAY_ID,
-			(DWORD_PTR)hwnd);
+	if(g_winver&WIN10RS1)
+	{
+		SetWindowSubclass(GetParent(hwnd), SubclassTrayProc,
+				SUBCLASSTRAY_ID, (DWORD_PTR)hwnd);
+	}
 	SetWindowSubclass(hwnd, SubclassProc, SUBCLASS_ID, 0);
 	
 	// don't accept double clicks
@@ -171,7 +179,11 @@ void EndClock(HWND hwnd)
 	
 	// restore window procedure
 	RemoveWindowSubclass(hwnd, SubclassProc, SUBCLASS_ID);
-	RemoveWindowSubclass(GetParent(hwnd), SubclassTrayProc, SUBCLASSTRAY_ID);
+	if(g_winver&WIN10RS1)
+	{
+		RemoveWindowSubclass(GetParent(hwnd), SubclassTrayProc,
+				SUBCLASSTRAY_ID);
+	}
 	
 #if TC_ENABLE_TASKBAR
 	RefreshTaskbar(hwnd);  // taskbar.c
diff --git a/source/dll/tcdll.h b/source/dll/tcdll.h
index 2d4233c..dac03c9 100644
--- a/source/dll/tcdll.h
+++ b/source/dll/tcdll.h
@@ -54,6 +54,8 @@ extern BOOL    g_bVisualStyle;
 extern BOOL    g_bNoClock;
 extern int     g_OrigClockWidth;
 extern int     g_OrigClockHeight;
+extern RECT    g_rcTaskbar;
+extern BOOL    g_bTaskbarPosChanging;
 extern BOOL    g_bLMousePassThru;
 
 /* ---------- wndproc.c ----------- */
diff --git a/source/dll/wndproc.c b/source/dll/wndproc.c
index 2ae95a7..1f9905d 100644
--- a/source/dll/wndproc.c
+++ b/source/dll/wndproc.c
@@ -70,11 +70,9 @@ LRESULT CALLBACK SubclassProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lPa
 		case WM_ERASEBKGND:
 			break;
 		
-#if 0
 		case (WM_USER+100):        // a message requesting for clock size
 			if(g_bNoClock) break;  // sent from parent window
-			return OnCalcRect(hwnd);
-#endif
+			return OnCalcRect(hwnd);  // (only before Win10RS1)
 		
 		case WM_WINDOWPOSCHANGING:  // size arrangement
 			if(g_bNoClock) break;
@@ -232,7 +230,7 @@ static void RearrangeNotifyArea(HWND hwnd, HWND hwndClock)
 	POINT posclk = {0, 0};
 	int wclock, hclock;
 	HWND hwndChild;
-
+	
 	size = OnCalcRect(hwndClock);
 	wclock = LOWORD(size);
 	hclock = HIWORD(size);
@@ -289,12 +287,29 @@ LRESULT CALLBACK SubclassTrayProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM
 			NMHDR *nmh = (NMHDR*)lParam;
 			HWND hwndClock = (HWND)dwRefData;
 
-			if(g_bNoClock || nmh->code != PGN_CALCSIZE)
+			if(g_bNoClock || nmh->code != PGN_CALCSIZE ||
+					g_bTaskbarPosChanging)
 				break;
 			ret = DefSubclassProc(hwnd, message, wParam, lParam);
 			RearrangeNotifyArea(hwnd, hwndClock);
 			return ret;
 		}
+		case WM_WINDOWPOSCHANGING:
+		{
+			RECT rc;
+			
+			GetWindowRect(GetParent(hwnd), &rc);
+			if (!EqualRect(&rc, &g_rcTaskbar))
+			{
+				g_rcTaskbar = rc;
+				g_bTaskbarPosChanging = TRUE;
+			}
+			else
+			{
+				g_bTaskbarPosChanging = FALSE;
+			}
+			break;
+		}
 	}
 	
 	return DefSubclassProc(hwnd, message, wParam, lParam);