use Win32::IE::Mechanize; 
my $mech = Win32::IE::Mechanize->new( visible => 0 ); 
$url = 'http://url/to/webpage'; 
$mech->get( $url );
$mech->success or die $mech->response->status_line;
$mech->get('javascript:Install()');
#DO something to hide the resulting msgBox/javascript:alert