Command Line Acrobat Reader - shifted characters!

In a .NET project we use Acrobat Reader with the command line option "/t" which allows to directly print a pdf to the desired printer. To start the printing we use a Process object with corresponding StartInfo.arguments and it is launched like this:

Process p = new Process();
[...]
p.Start();
System.Threading.Thread.Sleep(printerTimeout);
if (!p.HasExited)
{
  p.Kill();             
  System.Threading.Thread.Sleep(5000);
}

I开发者_如何学JAVAt happens that more than one pdf file must be printed in the same loop.

When only one pdf is printed, no problem. But for a specific installation and when more than one pdf files must be printed, some pages have shifted characters (in fact, all characters printed are shifted to one ASCII code, i.e. A becomes B, B becomes C etc.). But the originals pdf are correct and don't contain any shifted characters.

Is there a way to resolve this issue?

Thanks