This is the block where they check for an installed Adobe reader. If reader 11 is installed, the exception is thrown. If it's reader 10 it works.
try
{
AxAcroPDFLib.AxAcroPDF acrobat = new AxAcroPDFLib.AxAcroPDF();
IntPtr handle = acrobat.Handle;
acrobat.Dispose();
acrobat = null;
_isAcrobatPdfAvailable = true;
}
catch (Exception ex)
{
_isAcrobatPdfAvailable = false;
}