diff --git a/MUNGA_L4/L4VIDEO.cpp b/MUNGA_L4/L4VIDEO.cpp
index 94aed2e..03aee1a 100644
--- a/MUNGA_L4/L4VIDEO.cpp
+++ b/MUNGA_L4/L4VIDEO.cpp
@@ -1746,6 +1746,15 @@ DPLRenderer::DPLRenderer(
 	//}
 	//DEBUG_STREAM<<"**************************"<<std::endl<<"**************************"<<std::endl<<std::flush;
 	
+	//
+	// NULL before anything can leave this constructor early. It was not
+	// in the initialiser list, so until CreateDevice wrote it the member
+	// held whatever was on the stack - and the bail-out below it, plus
+	// the one that has always been here, both run the destructor and its
+	// SAFE_RELEASE(mDevice) over exactly that.
+	//
+	mDevice = NULL;
+
 	if (mPrimaryIndex == NULL)
 	{
 		DEBUG_STREAM<<"Unable to locate a suitable primary device index."<<std::endl<<std::flush;
@@ -1759,10 +1768,30 @@ DPLRenderer::DPLRenderer(
 		DEBUG_STREAM<<"Couldn't create HARDWARE_VERTEXPROCESSING device."<<std::endl<<std::flush;
 
 		V(gD3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd, D3DCREATE_SOFTWARE_VERTEXPROCESSING, &mPresentParams, &mDevice));
-		if (FAILED(hr))
-		{
-			PostQuitMessage(1);
-		}
+	}
+
+	//
+	// PostQuitMessage is a message, not a return. The fallback used to
+	// post one and then carry straight on into the Clear below, which
+	// dereferenced a device that was never created - so a machine that
+	// could not give us the mode we asked for died on an access
+	// violation instead of saying so.
+	//
+	// What was asked for goes in the line, because that is the question
+	// this failure raises: the back buffer is the requested size now,
+	// windowed as well as full-screen, so a request the adapter will not
+	// meet is the thing to look at first.
+	//
+	if (FAILED(hr) || mDevice == NULL)
+	{
+		DEBUG_STREAM << "DPLRenderer: no D3D device for a "
+			<< mPresentParams.BackBufferWidth << "x"
+			<< mPresentParams.BackBufferHeight
+			<< (mPresentParams.Windowed ? " windowed" : " full-screen")
+			<< " back buffer (hr=0x" << std::hex << hr << std::dec
+			<< ") - giving up\n" << std::flush;
+		PostQuitMessage(1);
+		return;
 	}
 
 	mDevice->Clear(0, NULL, D3DCLEAR_TARGET, 0xFF000000, 0.0f, 0);