diff --git a/rostests/apitests/gdi32api/tests/AddFontResourceEx.c b/rostests/apitests/gdi32api/tests/AddFontResourceEx.c
index 4dff4c483db..f10874f0ed6 100644
--- a/rostests/apitests/gdi32api/tests/AddFontResourceEx.c
+++ b/rostests/apitests/gdi32api/tests/AddFontResourceEx.c
@@ -1,12 +1,14 @@
+#define STAMP_DESIGNVECTOR (0x8000000 + 'd' + ('v' << 8))
 
 INT
 Test_AddFontResourceEx(PTESTINFO pti)
 {
 	WCHAR szFileName[MAX_PATH];
-	GetEnvironmentVariableW(L"systemroot", szFileName, MAX_PATH);
 
+	GetEnvironmentVariableW(L"systemroot", szFileName, MAX_PATH);
 	wcscat(szFileName, L"\\Fonts\\cour.ttf");
 
+	/* Test flags = 0 */
 	SetLastError(ERROR_SUCCESS);
 	TEST(AddFontResourceExW(szFileName, 0, 0) != 0);
 	TEST(GetLastError() == ERROR_SUCCESS);
@@ -15,5 +17,9 @@ Test_AddFontResourceEx(PTESTINFO pti)
 	TEST(AddFontResourceExW(szFileName, 256, 0) == 0);
 	TEST(GetLastError() == ERROR_INVALID_PARAMETER);
 
+	/* Test invalid pointer as last parameter */
+	TEST(AddFontResourceExW(szFileName, 0, (void*)-1) != 0);
+
+
 	return APISTATUS_NORMAL;
 }