So, does WWW::Mechanize->find_all_inputs find that link? Have you inspected your list of inputs? Does it find any other input fields? Is the HTML that WWW::Mechanize sees the HTML you expect?

What is the exact code you are using to find that "none of these are working"? I am asking that question because it helps me to replicate your situation. Please post a short, self-contained example of no more than 20 lines that reproduces the problem.

after this im not sure how else i can ask this question :/

use WWW::Mechanize;
use Storable;
use LWP;
use warnings;
my $loginpage = "http://www.homepage.org";
my $challenge = "http://www.homepage.org/test.htm";

my $username = 'username'; 
my $password = 'password';

my $mech = WWW::Mechanize->new();
$mech -> cookie_jar(HTTP::Cookies->new());
$mech -> get($loginpage);
$mech -> form_name('loginform');
$mech -> field ('username' => $username);
$mech -> field ('password' => $password);
$mech -> click ('btn_submit');
#navigate to challenge page

$mech->get( $challenge );

my @find_text = $mech->find_all_inputs(
        type  => 'text'
    );

for $boxes (@find_text) {
#if (length($boxes->value) > 100) {
     print $boxes->value();
 # }
}
[download]

yes, it is the correct page i check with print $mech->content();