apache crash with exec in php

i am try to convert some file with exec in php and get the return . i do this and this is work so successfully but if i run it for more than 10 times, the webserver (wampserver) get crash and i must restart server to continue ?

the only thing is unusually it's in my processes in taskmanager . if the convert files be successfully "cmd.exe" closed automatically after that, but if convert get worse the cmd.exe not closed and it remain in processes and i force it to close with "end process" but wampserver can not work until i restart it completely ?

is there any idea about solve apache or php or server problem ? System : wampserver version 2.0 on windows xp and 2003 server .

thanks

From serverfault $pageUsers[$entry.posts[0].author].name

• It sounds like there is a problem with how many requests it serves. The key, then(failing fixing the tool) is to restart the apache process after 9 times. Have you checked out the MaxRequestsPerChild setting under either prefork.c or worker.c? From httpd.conf:

  # MaxRequestsPerChild: maximum number of requests a server process serves
  

  Kevin M : I would. A setting of 0 means that it is unlimited. And if it turns out to be a bad idea because it dies(faster than it already does) or something similar, then you can change it back.
  From Kevin M

• thank you kevin, problem solved . my problem solved with change and re write my source code and server have not any problem . any way so thank you .

  Kevin M : Good idea, then, to accept an answer(mine), thus closing the question. People who see it in the list will know that it's been answered and that they shouldn't need to answer it anymore.
  From $pageUsers[$post.author].name