Hi Tamar One other thing happened to me when building GHC, very early. See below. I think the perl concerned is c:/msys64/usr/bin/perl. Any ideas? It seems non-fatal Thanks Simon perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LC_ALL = (unset), LANG = "ENG" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LC_ALL = (unset), LANG = "ENG" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LC_ALL = (unset), LANG = "ENG" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LC_ALL = (unset), LANG = "ENG" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LC_ALL = (unset), LANG = "ENG" are supported and installed on your system.