You've mentioned you're using a proxy.

You need to set up WWW:Mechanize to use your proxy. Ideally, you'll use the in-built OS options, but as a shortcut (to check if this actually is your problem) then just use:

my $mech = WWW::Mechanize -> new(); 
$mech -> http_proxy ( "Your_proxy_address:proxy_port" )
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I've also found enabling LWP debugging to be most useful when troubleshooting Mechanized scripts.

use LWP::Debug qw(+);
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