Hi Jos, in my %ENV there isn't my OS I tested it. I tried this sub restart_serv { my $OS = Win32::API::GetVersion(); $dwVersion = GetVersion(); if(!$dwVersion < 0x80000000) # windows 98 not windows NT #for (sort keys %ENV) { print "$_is $ENV{$_}\n" } $PROG = "c:\\cygwin\\usr\\sbin\\inetd.exe"; system($PROG) or die " je n'ai pas pu redémarrer : $!\n"; } But I have the following error : out of memory!!! Thanks