I'm trying to load a large PDF file and split every page out to a new filename... but memory usage goes up and up and up for every new file until the machine crashes.

It appears it's the new output file created that causes this,   how do you release that new file from memory after save?

Here's a test to show the problem:-

int MainDocID = QP2->SelectedDocument();

for(int a=0;a<1000;a++)

{

QP2->NewDocument();

fileBW = QP2->SelectedDocument();

QP2->SelectDocument(fileBW);

QP2->CopyPageRanges(MainDocID, _L("1-1"));

QP2->DeletePages(1,1); // remove new file 1st blank page

QP2->SaveToFile(tempBW);

}