See Encoding in Perl and Problem in compiling Text::IConv module on Windows for answers.

A Guide to Installing Modules says read README !

Prerequisites
-------------

Your system should be compliant with the Single UNIX Specification or
at least provide iconv_open(), iconv() and iconv_close() functions
compliant with it.

Note that the possible conversions and the quality of the conversions
depend on the available iconv conversion tables and algorithms, which
are in most cases supplied by the operating system vendor.  Some
systems also allow you to build your own tables (e.g., HP-UX, Tru64
UNIX, and AIX provide the genxlt(1) command).

It is also possible to use a separate iconv library such as GNU
libiconv package, just make sure that the desired library is found
(see <http://www.gnu.org/directory/localization/libiconv.html>).