HeapSetInformation and Low Fragmentation Heap

[MXL]

I am trying to set the heap to LFH mode on Windows XP Pro and Windows Server 2003 and I am getting the error ERROR_GEN_FAILURE (31) from GetLastError ()

ULONG ulEnableLFH = 2;
HANDLE hHeap = GetProcessHeap ();
HeapLock (hHeap);
if (HeapSetInformation(hHeap, HeapCompatibilityInformation, &ulEnableLFH, sizeof(ulEnableLFH)) == 0)
{
int nError = GetLastError ();
ASSERT (FALSE);
}
HeapUnlock (hHeap);

I am using DevStudio.net 2003 and C++ with statically linked libraries.