Having problems with screenshot code on windows vista

We have a program which renders some graphics with Direct3D9.
We am using some GDI code to take a screenshot of the window with these graphics in it.
We have a screenshot class that contains (among other things) these variables
HDC bufferDevice;
HBITMAP bufferBitmap;
uint bufferWidth;
uint bufferHeight;

When a screenshot is made, this function is called
void Screenshot::makeBuffer(HWND windowHandle)
{
RECT clientRect;
GetClientRect(windowHandle, &clientRect);

bufferWidth = clientRect.right - clientRect.left; // GetSystemMetrics (SM_CXSCREEN);
bufferHeight = clientRect.bottom - clientRect.top; // GetSystemMetrics (SM_CYSCREEN);

assert(bufferWidth > 0);
assert(bufferHeight > 0);

HDC targetDevice = GetDC (windowHandle);

if (bufferDevice)
{
DeleteObject (bufferBitmap);
DeleteDC (bufferDevice);
}

bufferDevice = CreateCompatibleDC (targetDevice);
bufferBitmap = CreateCompatibleBitmap (targetDevice, bufferWidth, bufferHeight);
HGDIOBJ oldObj = SelectObject (bufferDevice, bufferBitmap);

BitBlt (bufferDevice, 0, 0, bufferWidth, bufferHeight, targetDevice, 0, 0, SRCCOPY);

SelectObject(bufferDevice,oldObj);
ReleaseDC (windowHandle, targetDevice);
}

Then I queue this Screenshot object on another thread to do the actual write-to-file.
The write-to-file looks like this
bool Screenshot::writeToFile()
{
// Get bitmap data
RGBTRIPLE* bufferPixels = new RGBTRIPLE[bufferWidth*bufferHeight];
BITMAPINFO bufferBitmapInfo = {{sizeof(BITMAPINFOHEADER), bufferWidth, -(signed)bufferHeight, 1, 24, BI_RGB}};

if (!GetDIBits(bufferDevice, bufferBitmap, 0, bufferHeight, bufferPixels, &bufferBitmapInfo, DIB_RGB_COLORS))
{
delete[] bufferPixels;
return false;
}
// Construct rows
RGBTRIPLE** bufferScanlines = new RGBTRIPLE*[bufferHeight];
RGBTRIPLE* bufferScanlineIter = bufferPixels;
for (unsigned int scanlineIndex = 0; scanlineIndex < bufferHeight; scanlineIndex++)
{
bufferScanlines[scanlineIndex] = bufferScanlineIter;
bufferScanlineIter += bufferWidth;
}

DeleteObject (bufferBitmap);
bufferBitmap = 0;
DeleteObject (bufferDevice);
bufferDevice = 0;
<actual code for writing to file goes here>
}

On Windows XP, this code works flawlessly.
On one of our test machines running Windows Vista, if you take a second screenshot or a third or a forth, they always end up with the same content as the first one.
We have run a full run with application verifier (with "basics", "dirty stacks" and "dangerous APIs" turned on) on both the XP and Vista machines and no problems have shown up.

XP machine is running XP SP3 and everything listed on windows update.
Vista machine is Vista Ultimate x64 with SP1 and all updates.
Also failing on Vista Ultimate x86 with the same problem.
Any ideas on how to fix this (or even how to see whats going on inside GDI and what might be causing this) would be appreciated. If more information about the problem is required, I can provide it.
.

Relevant Pages

  • Re: Having problems with screenshot code on windows vista
    ... We am using some GDI code to take a screenshot of the window with these graphics in it. ... HDC bufferDevice; ... On one of our test machines running Windows Vista, if you take a second screenshot or a third or a forth, they always end up with the same content as the first one. ...
    (microsoft.public.win32.programmer.gdi)
  • Re: Just Installed Vista 7 Beta 64 Bit And...
    ... Windows Desktop Experience ... screenshot of the performance: ... you are posting to a Vista newsgroup not a Windows 7 one. ... is more like an updated version of Vista instead of a new OS. ...
    (microsoft.public.windows.vista.general)
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