My bet still is on the permission issue. Reading the CGI::Session documentation for ->new, it points to the ->errstr class method as a way of finding why the constructor might fail. So, why aren't you checking errors? What does the following write to the error log and/or output?

use strict;
#use English;
use Cwd qw(getcwd);
use CGI qw/:standard/;
use CGI::Carp qw(warningsToBrowser fatalsToBrowser);
#-- ppm install CGI::Session
use CGI::Session;

our $session;
our $query = new CGI();
our $perl_sessions = "C:/webtmp";
if (!(defined($query->cookie("wweb")))) {
        $session = new CGI::Session("driver:File", undef, {Directory=>
+$perl_sessions})
            or die "Couldn't create CGI session: " . CGI::Session->err
+str;
        $cookie = $q->cookie(-name   => "wweb",
                             -value  => $session->id);
    }
exit(0);
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Update Also looking at the CGI::Session documentation again, there is no CGI::Session::Driver::File but only CGI::Session::Driver::file, so maybe your error is in specifying "driver:File" instead of "driver:file".