diff --git a/programs/regedit/about.c b/programs/regedit/about.c
index e0e469efe19..6684dbe6346 100644
--- a/programs/regedit/about.c
+++ b/programs/regedit/about.c
@@ -29,6 +29,6 @@ void ShowAboutBox(HWND hWnd)
 {
     WCHAR title[64];
     HICON icon = LoadImageW( hInst, MAKEINTRESOURCEW(IDI_REGEDIT), IMAGE_ICON, 48, 48, LR_SHARED );
-    LoadStringW(hInst, IDS_APP_TITLE, title, COUNT_OF(title));
+    LoadStringW(hInst, IDS_APP_TITLE, title, ARRAY_SIZE(title));
     ShellAboutW(hWnd, title, NULL, icon);
 }
diff --git a/programs/regedit/edit.c b/programs/regedit/edit.c
index c982791b35c..db768b65cc6 100644
--- a/programs/regedit/edit.c
+++ b/programs/regedit/edit.c
@@ -54,8 +54,8 @@ static int vmessagebox(HWND hwnd, int buttons, int titleId, int resId, __ms_va_l
     WCHAR *str;
     int ret;
 
-    LoadStringW(hInst, titleId, title, COUNT_OF(title));
-    LoadStringW(hInst, resId, fmt, COUNT_OF(fmt));
+    LoadStringW(hInst, titleId, title, ARRAY_SIZE(title));
+    LoadStringW(hInst, resId, fmt, ARRAY_SIZE(fmt));
 
     FormatMessageW(FORMAT_MESSAGE_FROM_STRING|FORMAT_MESSAGE_ALLOCATE_BUFFER,
                    fmt, 0, 0, (WCHAR *)&str, 0, &va_args);
@@ -94,7 +94,7 @@ static BOOL change_dword_base(HWND hwndDlg, BOOL toHex)
     WCHAR buf[128];
     DWORD val;
 
-    if (!GetDlgItemTextW(hwndDlg, IDC_VALUE_DATA, buf, COUNT_OF(buf))) return FALSE;
+    if (!GetDlgItemTextW(hwndDlg, IDC_VALUE_DATA, buf, ARRAY_SIZE(buf))) return FALSE;
     if (!swscanf(buf, toHex ? percent_u : percent_x, &val)) return FALSE;
     wsprintfW(buf, toHex ? percent_x : percent_u, val);
     return SetDlgItemTextW(hwndDlg, IDC_VALUE_DATA, buf);
@@ -244,7 +244,7 @@ BOOL CreateKey(HWND hwnd, HKEY hKeyRoot, LPCWSTR keyPath, LPWSTR keyName)
 	goto done;
     }
 
-    if (!LoadStringW(GetModuleHandleW(0), IDS_NEWKEY, newKey, COUNT_OF(newKey))) goto done;
+    if (!LoadStringW(GetModuleHandleW(0), IDS_NEWKEY, newKey, ARRAY_SIZE(newKey))) goto done;
 
     /* try to find a name for the key being created (maximum = 100 attempts) */
     for (keyNum = 1; keyNum < 100; keyNum++) {
@@ -460,7 +460,7 @@ BOOL CreateValue(HWND hwnd, HKEY hKeyRoot, LPCWSTR keyPath, DWORD valueType, LPW
 	return FALSE;
     }
 
-    if (!LoadStringW(GetModuleHandleW(0), IDS_NEWVALUE, newValue, COUNT_OF(newValue))) goto done;
+    if (!LoadStringW(GetModuleHandleW(0), IDS_NEWVALUE, newValue, ARRAY_SIZE(newValue))) goto done;
 
     /* try to find a name for the value being created (maximum = 100 attempts) */
     for (valueNum = 1; valueNum < 100; valueNum++) {
diff --git a/programs/regedit/framewnd.c b/programs/regedit/framewnd.c
index 94da217045a..804573e0c00 100644
--- a/programs/regedit/framewnd.c
+++ b/programs/regedit/framewnd.c
@@ -167,7 +167,7 @@ static void update_new_items_and_copy_keyname(HMENU hMenu, WCHAR *keyName)
     if (!keyName)
         state = MF_GRAYED;
 
-    for (i = 0; i < COUNT_OF(items); i++)
+    for (i = 0; i < ARRAY_SIZE(items); i++)
         EnableMenuItem(hMenu, items[i], state | MF_BYCOMMAND);
 }
 
@@ -469,7 +469,7 @@ static BOOL ImportRegistryFile(HWND hWnd)
 
     InitOpenFileName(hWnd, &ofn);
     ofn.Flags |= OFN_ENABLESIZING;
-    LoadStringW(hInst, IDS_FILEDIALOG_IMPORT_TITLE, title, COUNT_OF(title));
+    LoadStringW(hInst, IDS_FILEDIALOG_IMPORT_TITLE, title, ARRAY_SIZE(title));
     ofn.lpstrTitle = title;
     if (GetOpenFileNameW(&ofn)) {
         if (!import_registry_filename(ofn.lpstrFile)) {
@@ -498,7 +498,7 @@ static BOOL ExportRegistryFile(HWND hWnd)
     WCHAR title[128];
 
     InitOpenFileName(hWnd, &ofn);
-    LoadStringW(hInst, IDS_FILEDIALOG_EXPORT_TITLE, title, COUNT_OF(title));
+    LoadStringW(hInst, IDS_FILEDIALOG_EXPORT_TITLE, title, ARRAY_SIZE(title));
     ofn.lpstrTitle = title;
     ofn.Flags = OFN_ENABLETEMPLATE | OFN_ENABLEHOOK | OFN_EXPLORER | OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;
     ofn.lpfnHook = ExportRegistryFile_OFNHookProc;
@@ -676,7 +676,7 @@ static INT_PTR CALLBACK addtofavorites_dlgproc(HWND hwndDlg, UINT uMsg, WPARAM w
             item.mask = TVIF_HANDLE | TVIF_TEXT;
             item.hItem = selected;
             item.pszText = buf;
-            item.cchTextMax = COUNT_OF(buf);
+            item.cchTextMax = ARRAY_SIZE(buf);
             SendMessageW(g_pChildWnd->hTreeWnd, TVM_GETITEMW, 0, (LPARAM)&item);
 
             EnableWindow(GetDlgItem(hwndDlg, IDOK), FALSE);
@@ -1065,10 +1065,10 @@ LRESULT CALLBACK FrameWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lPa
         CreateWindowExW(0, szChildClass, captionW, WS_CHILD | WS_VISIBLE,
                         CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
                         hWnd, NULL, hInst, 0);
-        LoadStringW(hInst, IDS_EXPAND, expandW, COUNT_OF(expandW));
-        LoadStringW(hInst, IDS_COLLAPSE, collapseW, COUNT_OF(collapseW));
-        LoadStringW(hInst, IDS_EDIT_MODIFY, modifyW, COUNT_OF(modifyW));
-        LoadStringW(hInst, IDS_EDIT_MODIFY_BIN, modify_binaryW, COUNT_OF(modify_binaryW));
+        LoadStringW(hInst, IDS_EXPAND, expandW, ARRAY_SIZE(expandW));
+        LoadStringW(hInst, IDS_COLLAPSE, collapseW, ARRAY_SIZE(collapseW));
+        LoadStringW(hInst, IDS_EDIT_MODIFY, modifyW, ARRAY_SIZE(modifyW));
+        LoadStringW(hInst, IDS_EDIT_MODIFY_BIN, modify_binaryW, ARRAY_SIZE(modify_binaryW));
         break;
     case WM_COMMAND:
         if (!_CmdWndProc(hWnd, message, wParam, lParam))
diff --git a/programs/regedit/listview.c b/programs/regedit/listview.c
index 0934e03a39e..404699fab8c 100644
--- a/programs/regedit/listview.c
+++ b/programs/regedit/listview.c
@@ -361,7 +361,7 @@ HWND CreateListView(HWND hwndParent, UINT id)
     WCHAR ListView[] = {'L','i','s','t',' ','V','i','e','w',0};
 
     /* prepare strings */
-    LoadStringW(hInst, IDS_REGISTRY_VALUE_NOT_SET, g_szValueNotSet, COUNT_OF(g_szValueNotSet));
+    LoadStringW(hInst, IDS_REGISTRY_VALUE_NOT_SET, g_szValueNotSet, ARRAY_SIZE(g_szValueNotSet));
 
     /* Get the dimensions of the parent window's client area, and create the list view control.  */
     GetClientRect(hwndParent, &rcClient);
diff --git a/programs/regedit/main.c b/programs/regedit/main.c
index 19d720d4d22..62fd616b519 100644
--- a/programs/regedit/main.c
+++ b/programs/regedit/main.c
@@ -172,8 +172,8 @@ int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPWSTR lpCmdLi
     }
 
     /* Initialize global strings */
-    LoadStringW(hInstance, IDS_APP_TITLE, szTitle, COUNT_OF(szTitle));
-    LoadStringW(hInstance, IDS_REGISTRY_DEFAULT_VALUE, g_pszDefaultValueName, COUNT_OF(g_pszDefaultValueName));
+    LoadStringW(hInstance, IDS_APP_TITLE, szTitle, ARRAY_SIZE(szTitle));
+    LoadStringW(hInstance, IDS_REGISTRY_DEFAULT_VALUE, g_pszDefaultValueName, ARRAY_SIZE(g_pszDefaultValueName));
 
     /* Store instance handle in our global variable */
     hInst = hInstance;
diff --git a/programs/regedit/main.h b/programs/regedit/main.h
index 788de1a5098..1d0109f9e5a 100644
--- a/programs/regedit/main.h
+++ b/programs/regedit/main.h
@@ -30,7 +30,7 @@
 
 #define	SPLIT_WIDTH	5
 
-#define COUNT_OF(a) (sizeof(a)/sizeof(a[0]))
+#define ARRAY_SIZE(A) (sizeof(A)/sizeof(*A))
 
 #define MAX_NEW_KEY_LEN 128
 
diff --git a/programs/regedit/treeview.c b/programs/regedit/treeview.c
index 4bbec40df8d..86224e231b1 100644
--- a/programs/regedit/treeview.c
+++ b/programs/regedit/treeview.c
@@ -521,7 +521,7 @@ HTREEITEM InsertNode(HWND hwndTV, HTREEITEM hItem, LPWSTR name)
             item.mask = TVIF_HANDLE | TVIF_TEXT;
             item.hItem = hNewItem;
             item.pszText = buf;
-            item.cchTextMax = COUNT_OF(buf);
+            item.cchTextMax = ARRAY_SIZE(buf);
             if (!TreeView_GetItemW(hwndTV, &item)) continue;
             if (lstrcmpW(name, item.pszText) == 0) break;
         }