On Sep 14, 12:05 pm, painulya... / gmail.com wrote: > Hi All, > > I have a console application. In windows 2000, _popen() is returning > invalid handle. I checked the same app with 2003 Server, its working > fine. Are you talking about IO.popen? I didn't think Ruby used _popen() behind the scenes, but it's been a while since I looked. The _popen() function is basically broken on Windows. From MSDN: "If used in a Windows program, the _popen function returns an invalid file pointer that will cause the program to hang indefinitely. _popen works properly in a Console application. To create a Windows application that redirects input and output, see "Creating a Child Process with Redirected Input and Output" in the Platform SDK." Regards, Dan