diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index 26ac9a9..78bc7dc 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -376,7 +376,7 @@ LRESULT MainWindow::HandleMessage(UINT uMsg, WPARAM wParam, LPARAM lParam)
         int size = dnslen(keychars) + 1, i;
         LPWSTR s;
         if (m_keychars)
-            delete m_keychars;
+            delete [] m_keychars;
         m_keychars = new WCHAR[size];
         for (i = 0; i < size; ++i) {
             WORD scan = VkKeyScanEx(keychars[i], hklQWERTY);
diff --git a/src/PianoControl.cpp b/src/PianoControl.cpp
index 168d6f3..b3a7aca 100644
--- a/src/PianoControl.cpp
+++ b/src/PianoControl.cpp
@@ -76,7 +76,7 @@ void PianoControl::SetOctaves(int octaves)
         newname = new type[7 * octaves];\
         if (store) {\
             memcpy(newname, store, min(this->octaves * 7, 7 * octaves) * sizeof(type));\
-            delete store;\
+            delete [] store;\
         } else \
             memset(newname, 0, 7 * octaves * sizeof(type));\
         store = newname;\
@@ -296,7 +296,7 @@ void PianoControl::PaintContent(PAINTSTRUCT *pps)
         int bufidx = 0; \
         if (bufsize < bufneed) { \
             if (szBuffer) \
-                delete szBuffer; \
+                delete [] szBuffer; \
             szBuffer = new WCHAR[bufneed]; \
         } \
         for (LPCWSTR c = store[i]; *c; c++) { \