A Guide to Installing Modules

• turn on debug/logging, increase verbosity... cpan> o debug all http://perldoc.perl.org/CPAN.html#Debugging
• Or

  $ cpan
  
  cpan shell -- CPAN exploration and modules installation (v1.9800)
  Enter 'h' for help.
  
  cpan[1]> look Tk
  [download]

• Or same using cpanp z Tk