Dear Members, I am very new to both R and bioconductor. I am working with illumina microarray data from ArrayExpress. (E-TABM-421, it's in the proivate section. so may not accessible to everyone). I have downloaded the processed zip file, .adrf , .sdrf, .idf files from the directory. Using the Arrayexpress "procset" method I have managed to create an ExpressionSet object. Problems: 1. Now I am not sure how can I use this ExpressionSet object for further analysis of the Data? 2. Is it possible to convert this ExpressionSet object to object of some other classes (i.e. Lumi)? 3. If possible can you please show a simple example ? I would like to thanks in advance for any sort of help and suggestion. regards, Md.Mamunur Rashid below is the R script I have used and few results: > library(ArrayExpress) > etabm421 <- list(path = ".",rawadata = NULL, rawfiles = NULL, procdata = "E-TABM-421.processed.zip",procfile = "E-TABM-421-processed-data-1583036605.txt",sdrf = "E-TABM-421.sdrf.txt", idf = "E-TABM-421.idf.txt", adf = "A-MEXP-931.adf.txt") > cn = getcolproc(ETABM421) > cn [1] "Reporter REF" "BeadStudio:AVG_Signal" [3] "BeadStudio:Detection Pval" > proset = procset(ETABM421,cn[2]) > slotNames(proset) [1] "assayData" "phenoData" "featureData" "experimentData" [5] "annotation" ".__classVersion__"