diff --git a/rostests/apitests/w32knapi/ntgdi/NtGdiCreateCompatibleDC.c b/rostests/apitests/w32knapi/ntgdi/NtGdiCreateCompatibleDC.c
index a53821b5889..3597eb67dca 100644
--- a/rostests/apitests/w32knapi/ntgdi/NtGdiCreateCompatibleDC.c
+++ b/rostests/apitests/w32knapi/ntgdi/NtGdiCreateCompatibleDC.c
@@ -22,6 +22,8 @@ Test_NtGdiCreateCompatibleDC(PTESTINFO pti)
 	hObj = SelectObject(hDC, GetStockObject(WHITE_PEN));
 	TEST(hObj == GetStockObject(BLACK_PEN));
 
+	TEST(NtGdiDeleteObjectApp(hDC) != 0);
+
 	return APISTATUS_NORMAL;
 }
 
diff --git a/rostests/apitests/w32knapi/ntgdi/NtGdiDeleteObjectApp.c b/rostests/apitests/w32knapi/ntgdi/NtGdiDeleteObjectApp.c
index ef4daa228bd..0084b109a9a 100644
--- a/rostests/apitests/w32knapi/ntgdi/NtGdiDeleteObjectApp.c
+++ b/rostests/apitests/w32knapi/ntgdi/NtGdiDeleteObjectApp.c
@@ -16,7 +16,7 @@ Test_NtGdiDeleteObjectApp(PTESTINFO pti)
     TEST(NtGdiDeleteObjectApp((PVOID)(GDI_HANDLE_STOCK_MASK | 0x1234)) == 1);
     TEST(GetLastError() == 0);
 
-    /* Delete a DC */
+    /* Delete a compatible DC */
     SetLastError(0);
     hdc = CreateCompatibleDC(NULL);
     ASSERT(IsHandleValid(hdc) == 1);
@@ -24,6 +24,26 @@ Test_NtGdiDeleteObjectApp(PTESTINFO pti)
     TEST(GetLastError() == 0);
     TEST(IsHandleValid(hdc) == 0);
 
+    /* Delete a display DC */
+    SetLastError(0);
+    hdc = CreateDC("DISPLAY", NULL, NULL, NULL);
+    ASSERT(IsHandleValid(hdc) == 1);
+    TEST(NtGdiDeleteObjectApp(hdc) != 0);
+    TEST(GetLastError() == 0);
+    TEST(IsHandleValid(hdc) == 1);
+    TEST(SelectObject(hdc, GetStockObject(WHITE_PEN)) == NULL);
+    TESTX(GetLastError() == ERROR_INVALID_PARAMETER, "GetLasterror returned 0x%08x\n", (unsigned int)GetLastError());
+
+    /* Once more */
+    SetLastError(0);
+    hdc = GetDC(0);
+    ASSERT(IsHandleValid(hdc) == 1);
+    TEST(NtGdiDeleteObjectApp(hdc) != 0);
+    TEST(GetLastError() == 0);
+    TEST(IsHandleValid(hdc) == 1);
+    TEST(SelectObject(hdc, GetStockObject(WHITE_PEN)) == NULL);
+    TESTX(GetLastError() == ERROR_INVALID_PARAMETER, "GetLasterror returned 0x%08x\n", (unsigned int)GetLastError());
+
     /* Delete a brush */
     SetLastError(0);
     hbrush = CreateSolidBrush(0x123456);