Error starting with Ghostscript. - can't open EPS file with GIMP

I can't open EPS file with GIMP. When I try I receive always the same
error message.

- Error starting Ghostscript. Make sure that Ghostscript is installed
and - if necessary - use the environment variable GS_PROG to tell GIMP
about its location.
(Failed to execute child process (No such file or directory)).
-
I have installed Ghostscript on my computer.
I dont know what could be the real problem.
Thanks for the help and advice
Nándor