Duncan Murdoch and I have been working on Vista compatibility. The first build of R-2.5.1-win32.exe was built with a version of the installer that had some compatibility issues, and it has been rebuilt under the latest version. What now happens is that if you want to install R in an adminstrative area you need to select 'Run as Administrator' when running the installer: otherwise the default installation directory offered will be in your user area (e.g. c:/Users/ripley/Documents). The Tcl support files came with obsolete Winhelp 4 .hlp files that are not readable under Vista, and .chm help has been added. (As from the next release .hlp will be dropped.) Rtools.exe has also been rebuilt with newer versions of the tools that work on Vista. There is still a compiler path issue, and you need to add c:\Rtools\MinGW\libexec\gcc\mingw\3.4.5 (or similar) to your path. When that is done I have successfully built and run R-patched and R-devel on 64-bit Vista. -- Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595