The reason the 401 error occurs is because you are using ActivePerl 5.14 which is no longer considered as a Community Edition. This means you no longer have access to the PPM server to install modules unless you buy a license from ActiveState.
See here for reference http://community.activestate.com/taxonomy/term/515
You have several options:
- You could buy an ActiveState Business Edition License which will give your access to the PPM repository again.
- If you have MinGW and dmake installed, you can install this module from CPAN instead. Just enter
cpan Date::Manip
in the command-line. - Upgrade to the latest version of ActivePerl. (But you'll have the same problem again when this version expires.)
- You could install another Perl distribution, like Strawberry Perl.