Access cmd via PHP

Hi there

I try to access the command line via PHP (5.4.9) on my Server 2008 R2. When i run the following php code:

<?php
$result = 0;$resultstr = system('echo %PATH%', $result);echo $resultstr;
?>

When i execute the code i got: PHP Warning: system(): Unable to fork [echo %PATH%]

I already tried these things:

• The Website and the assigned APP-Pool are running with an local administrator account
• Give Everyone permissions to execute cmd.exe
• Copying the cmd.exe to the same folder where the .php File is.

Does anyone know a solution for my problem?

Thanks very much :)

Regards,

Simon