I would like to use vsn normalization through the affylmGUI package. Is this possible by customizing the menu? I followed the guidelines in the documentation of the affylmGUI package. I have changed the affylmGUI-menus.txt file in the etc folder. item normalizeMenu command "vsn" vsn I have also copied the vsn.R source file to the etc folder. Is this necessary or should more source files/the complete package be copied to that folder? I get the following error: Error in eval(expr,envir,enclos): object "vsn" not found Thanks for any suggestions, Stefanie -- ================================================================== Stefanie De Bodt, PhD VIB Department of Plant Systems Biology, UGent Bioinformatics and Evolutionary Genomics Technologiepark 927 B-9052 Gent Belgium Tel: 32 (0)9 3313692 Website: http://bioinformatics.psb.ugent.be