As a way to learn the beadarray package (I'm new to microarray analysis and have some Illumina microarray summary data to analyze) I've tried the example in the document "bead-summary data using beadarray". As indicated in the document I downloaded and unzipped the example summary data from: http://www.compbio.group.cam.ac.uk/Resources/illumina/BeadSummaryExamp le.zip However, I get the following error message when issuing the example commands: > setwd('C:/Projects/beadarray/BeadSummaryExample') > library(beadarray) > dataFile <- "SampleProbeProfile.txt" > sampleSheet <- "SampleSheet.csv" > qcFile <- "ControlGeneProfile.txt" > BSData = readBeadSummaryData(dataFile = dataFile, qcFile = qcFile, sampleSheet = sampleSheet, controlID = "TargetID") Error in .nextMethod(e1, e2) : comparison of these types is not implemented I'm using beadarray 1.10.0 and R 2.8.0 on windows XP (session info below). I'd appreciate any help! Juan Pablo Lewinger Department of Preventive Medicine University of Southern California > sessionInfo() R version 2.8.0 (2008-10-20) i386-pc-mingw32 locale: LC_COLLATE=English_United States.1252;LC_CTYPE=English_United States.1252;LC_MONETARY=English_United States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252 attached base packages: [1] tools stats graphics grDevices utils datasets methods base other attached packages: [1] beadarray_1.10.0 sma_0.5.15 hwriter_0.93 geneplotter_1.14.0 lattice_0.17-17 annotate_1.14.1 [7] Biobase_1.14.1 limma_2.9.17 loaded via a namespace (and not attached): [1] AnnotationDbi_1.2.2 DBI_0.2-4 grid_2.8.0 KernSmooth_2.22-22 RColorBrewer_1.0-2 RSQLite_0.7-1