problem with grep

[Stanke, Fred]

I am not a unix guy, but I've come to depend on emacs after using it for 
decades.

I have a problem, grep does not work.  How do I fix it?

-*- mode: grep; default-directory: "c:/Users/fstanke/Documents/" -*-
Grep started at Wed Apr 18 17:14:36

grep  -n cycles *.txt NUL
'grep' is not recognized as an internal or external command,
operable program or batch file.

Grep exited abnormally with code 1 at Wed Apr 18 17:14:38