Print from IE browser

Hello! I am trying to batch print a set of pdf's from IE browser. I included the acropdf object (from Adobe 7) in the .asp and wrote a function PrintPDF (below) to 'silent' print the files. I dynamically build another function with repeated calls to PrintPDF(), but only the first file prints, unless I uncomment the alert() statement. Does anyone know why? Having the user acknowledge each print job kinda defeats the purpose of batch printing.
 
In this example, only file1.pdf prints, the others are ignored:
 
function PrintPDF(pdfUrl)
{
PDF.SRC=pdfUrl;
PDF.PrintAll();
// alert(pdfUrl);
}
 
function BatchPrintPDF()
{
PrintPDF('\\\\myserver\\mypath\\file1.pdf');
PrintPDF('\\\\myserver\\mypath\\file2.pdf');
PrintPDF('\\\\myserver\\mypath\\file3.pdf');
}
 
Thanks for your help!
Sophia