diff --git a/reactos/lib/comctl32/tooltips.c b/reactos/lib/comctl32/tooltips.c
index 39d981b3897..c16fd7e6f02 100644
--- a/reactos/lib/comctl32/tooltips.c
+++ b/reactos/lib/comctl32/tooltips.c
@@ -2400,7 +2400,7 @@ TOOLTIPS_NCCreate (HWND hwnd, WPARAM wParam, LPARAM lParam)
     DWORD dwStyle = GetWindowLongW (hwnd, GWL_STYLE);
     DWORD dwExStyle = GetWindowLongW (hwnd, GWL_EXSTYLE);
 
-    dwStyle &= 0x0000FFFF;
+    dwStyle &= ~(WS_CHILD | /*WS_MAXIMIZE |*/ WS_BORDER | WS_DLGFRAME);
     dwStyle |= (WS_POPUP | WS_BORDER | WS_CLIPSIBLINGS);
 
     /* WS_BORDER only draws a border round the window rect, not the
diff --git a/reactos/lib/comctl32/treeview.c b/reactos/lib/comctl32/treeview.c
index 189eff592d4..2aaf41e2a4e 100644
--- a/reactos/lib/comctl32/treeview.c
+++ b/reactos/lib/comctl32/treeview.c
@@ -565,7 +565,7 @@ TREEVIEW_SendTreeviewNotify(TREEVIEW_INFO *infoPtr, UINT code, UINT action,
     TRACE("code:%d action:%x olditem:%p newitem:%p\n",
 	  code, action, oldItem, newItem);
 
-    ZeroMemory(&nmhdr, sizeof(NMTREEVIEWA));
+    ZeroMemory(&nmhdr, sizeof(NMTREEVIEWW));
 
     nmhdr.hdr.hwndFrom = hwnd;
     nmhdr.hdr.idFrom = GetWindowLongPtrW(hwnd, GWLP_ID);