Hi, YHC_build(["src\packages\haskell98-1.0\Ix.hbc"], ["src\packages\haskell98-1.0\Ix .hs"]) inst\bin\yhc.exe -i src/packages/haskell98-1.0/ -d src/packages/haskell98-1.0/ - c src\packages\haskell98-1.0\Ix.hs yhc.exe: Error: File not found, YHC.Internal Reason: imported from Ix Looked in: D:\sources\yhc\11_sep_2006\yhc-devel\src\packages\haskell98-1.0\ D:\sources\yhc\11_sep_2006\yhc-devel/inst/lib\yhc\packages\yhc-base\1.0 Thats a most recent version, scons fullclean, scons (core=1) Thanks Neil