Here is mine

#!/usr/bin/perl --
use strict; use warnings;
use Win32::GUI();
use Win32::API;
Win32::API->Import('kernel32','BOOL SetConsoleIcon(HWND icon)');

@ARGV or @ARGV = map { glob $_ }
    "C:/Progra~1/*.ico",
    "C:/Progra~1/*/*.ico",
    "C:/Progra~1/*/*/*.ico",
    "C:/Progra~1/*/*/*/*.ico",
#~     "C:/Progra~1/*/*/*/*/*.ico",
    "C:/WINDOWS/*/*.ico",
    "C:/WINDOWS/*/*/*.ico",
    "C:/WINDOWS/*/*/*/*.ico",
#~     "C:/WINDOWS/*/*/*/*/*.ico",
#~     "C:/WINDOWS/*/*/*/*/*/*.ico",
#~     "C:/WINDOWS/*/*/*/*/*/*/*.ico",
;;;;

    
for my $file ( @ARGV ){
    print "$file\n";
    eval {
        my $icon = Win32::GUI::Icon->new( $file )
            or die sprintf qq/ErrIcon \$!(%d)(%s)\n\$^E(%d)(%s)\nGLS(%
+d)(%s)/,
                $!,$!,$^E,$^E,
                Win32::GetLastError(),
                Win32::FormatMessage(Win32::GetLastError())
            ;;;;; 
        SetConsoleIcon( $icon->{-handle} )
            or die sprintf qq/ErrSet \$!(%d)(%s)\n\$^E(%d)(%s)\nGLS(%d
+)(%s)/,
                $!,$!,$^E,$^E,
                Win32::GetLastError(),
                Win32::FormatMessage(Win32::GetLastError())
            ;;;;; 
        1;
    } or warn "$@\n\n";
    sleep 1;
}

SetConsoleIcon( undef );## restore
__END__
$ perl sicon.pl sicon.pl perlmonks.favicon.ico sicon.pl
sicon.pl
ErrIcon $!(2)(No such file or directory)
$^E(0)()
GLS(0)(The operation completed successfully.
) at sicon.pl line 25.


perlmonks.favicon.ico
sicon.pl
ErrIcon $!(2)(No such file or directory)
$^E(0)()
GLS(0)(The operation completed successfully.
) at sicon.pl line 25.
[download]

Obviously sicon.pl isn't an .ico file

Looking at these results and Win32::GUI::Icon docs, it is now obvious that it doesn't preserve $^E from the 2-3 ways it tries to load the file, so $^E ends up being uninformative

FormatMessage() OTOH assumes 0 means success where as $^E doesn't

Since this program works for me for about a dozen icon files I find in program files

I must assume there is something wrong with your box2.ico

good luck figuring it out :) You might hack on some GUI.xs to insert informative diagnostics, or hit up MSDN for specs regarding icon files so you can compare them to box2.ico ...