Problems: -the standard PATH is not fit to compile 64bit stuf, so unset it: unsetenv PATH -we did not have pkg-config installed, used yast to install it -we did not have these environment variables set: setenv LD_LIBRARY_PATH /geninf/prog/VIZ64/lib/graphviz setenv PKG_CONFIG_PATH /geninf/prog/VIZ64/lib/pkgconfig/ we installed graphvix 2.6 and rgraphviz 1.8 we installed in R using: source("http://bioconductor.org/getBioC.R") getBioC("Rgraphviz") and then: library(Rgraphviz) works fine Harm Nijveen Harm.nijveen@wur.nl Wageningen [[alternative HTML version deleted]]