problems printing a list of pdf

Later a user selects a list of documents and prints them, but 'sometimes' documents with more than 1 page have a problem; the first page is ok, the second is not printed and instead you get a blank page. The doc is ok, if you select it again and print it alone, it works.

For example, yesterday they printed a list of 50 docs, and the 32nd (2-page doc) was printed like that, first page ok and a blank page.

I think it could be a network problem or a printer problem, maybe the print queue is too long. Should I slow the process adding some delay ?

 

thanks

I use the DLL with MS Visual C++ 6.0 and i don't use multithreading.
I just use my PrintQuick class with some functions.

 

PrintQuick::PrintQuick()
{
   pdf = new QuickPDFDLL0812(...path...);
   pdf->UnlockKey(...);
   pdf->SetPageSize(L"A4");
}
PrintQuick::LoadFile(wPathFile)
{
    int iRet = pdf->LoadFromFile(wPathFile,L"");
}
PrintQuick::RemoveFile()
{
    int iId = pdf->SelectedDocument();
    pdf->RemoveDocument(iId);
}
PrintQuick::PrintFile(printer)
{
     std::wstring wQuickPrn = pdf->NewCustomPrinter(printer);
     pdf->SetupCustomPrinter(wQuickPrn,1,DMPAPER_A4);
     int iNum = pdf->PageCount();
     int iOptions = pdf->PrintOptions(1,0,L"Print Options"); // fit to page
     pdf->PrintDocument(wQuickPrn,1,iNum,iOptions);
}
PrintQuick::~PrintQuick()
{
   delete pdf;
}

 

When the user selects a list of docs to print, there's just a loop:

for (iDoc=0;iDoc<iMaxDoc;iDoc++)
{
 CPrintQuick printPdf;
 printPdf.LoadFile(ListDoc.GetAt(iDoc));
 printPdf.PrintFile(printerName);
 printPdf.RemoveFile();
}

 

thanks