Checking if your kit is complete... Looks good Writing Makefile for Socket6 cp Socket6.pm blib\lib/Socket6.pm D:\cpanrun\build\5-6-1\bin\perl.exe -Id:\cpanrun\build\5-6-1\lib -Id:\cpanrun\build\5-6-1\lib DNMAKE : fatal error U1077: 'cl' : return code '0x2' Stop. emap D:\cpanrun\build\5-6-1\lib\ExtUtils\typemap Socket6.xs > Socket6.xsc && D:\cpanrun\build\5-6-1\bin\perl.exe -Id:\cpanrun\build\5-6-1\lib -Id:\cpanrun\build\5-6-1\lib -MExtUtils::Command -e mv Socket6.xsc Socket6.c cl -c -nologo -O1 -MD -Zi -DNDEBUG -DWIN32 -D_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DPERL_MSVCRT_READFIX -O1 -MD -Zi -DNDEBUG -DVERSION=\"0.19\" -DXS_VERSION=\"0.19\" -ID:\cpanrun\build\5-6-1\lib\CORE Socket6.c Socket6.c Socket6.xs(44) : fatal error C1189: #error : Microsoft Platform SDK (Aug. 2001) or later required.