'findstr' is not recognized as an internal or external command

On Windows operating system, while executing a batch file or a command, if you are getting following error:

'findstr' is not recognized as an internal or external command

it means, that you are missing C:\Windows\System32 in your path. On Win 7, go to My Computer --> Properties --> Advanced System settings --> Environment Variables --> System Variables --> Path and at the end of current value, add the missing path "C:\Windows\System32".

It worked for me, should also work for you :-)