Re: [Haskell-cafe] unable to load package `regex-posix-0.94.2' (On Vista x64)

Maybe you want to hide the old version of regex-posix:

ghc-pkg hide regex-posix-0.94.2

http://www.haskell.org/ghc/docs/7.0.1/html/users_guide/packages.html Note - I don't use cabal install myself so this might not be the right way to do things, however "ghc-pkg hide ..." is reversible with "ghc-pkg expose ..." so I can't see it doing any harm.