shellexecute - command is not running from php script using shell_exec() or system() or exec() functions -

I am working on a Windows server and I'm able to run commands from a command prompt.

  C: & gt; % Convertxls% {some args ....}  

But when I run the same command from the php script

  * shell_exec (% convertxls%. .. 2 & gt; and 1); *  

This gives me an error

% convertxls% is not recognized as an internal or external command, operable program or batch file.

I think that when I am running a command prompt from a command prompt, it goes to the user who is logged in. And when I run a php script that runs it for the "www" user

* NOTE: I have not written the entire order.

Provide the full path to the executable.