I get an email from outside the company, in this case a test hotmail account, and when going into OTRS and replying to it, when clicking send, I get this error:

ERROR: OTRS-CGI-10 Perl: 5.8.8 OS: linux Time: Wed Apr  2 09:51:14 2008

Message: Can't send to: kitkatuser@hotmail.com! Enable debug for more info!

Traceback (24174):
   Module: Kernel::System::Email::SMTP::Send (v1.14) Line: 98
   Module: Kernel::System::Email::Send (v1.31.2.1) Line: 498
   Module: Kernel::System::Ticket::Article::ArticleSend (v1.147) Line: 1610
   Module: Kernel::Modules::AgentTicketCompose::Run (v1.30.2.2) Line: 364
   Module: Kernel::System::Web::InterfaceAgent::Run (v1.23) Line: 670
   Module: /opt/otrs/bin/cgi-bin/index.pl (v1.81) Line: 47

How do I enable debug to find out more about this issue and perhaps fix it…

Thanks

Nelson