Lpr error 64 bit windows

Using lpr client from the command line has always been available on Windows 32 bit systems. In attempting to use this on a 64 bit system, I get "command not found".
What do I need to do in order to do lpr -S -P from the command line on Windows 64?
Thanks,

No,

I am just trying to invoke a DOS command (lpr) from a C appl using the system() call.
I found that you have to enable the "LPR Port Monitor".
This via the "Control Panel/Programs and Features/Turn Windows features on or off".
I can now do
lpr -S 10.10.10.10 -P Printer test.fil
from a DOS prompt and it works.
When I try to do the same thing in an application from a system call
system("lpr -S 10.10.10.10 -P Printer test.fil" );
I get
'lpr' is not recognized as an internal or external command