You should update (sometimes force install) AT LEAST: IO (getting tar.gz from search.cpan.org or anywhere; because your CPAN shell doesn’t work!) Storable Scalar::Util Cwd (your Cwd is now pure perl!!) Encode (reload index and install it again if the test fails) This post may help you. details are below ( written in LANG=ja_JP, but you will understand it!) [danjou@sylvia] $ perl -MIO IO object ver