Hi List, I installed bioconductor and the ecolicdf package under Unix. I get the following message when I type: > Data<-ReadAffy() > eset<-rma(Data) Error in .local(object, ...) : Information about probe locations for Ecoli could not be found. Try downloading the ecolicdf package from http://www.bioconductor.org/data/cdfenvs/cdfenvs.html I use the CEL files from Affy Antisense E. coli chip. Does anybody know how I can solve this problem?? Thanks in advance Tina ------------------------------------------------------------------- Bettina Harr, PhD Department of Ecology and Evolution University of Chicago 1101 East 57th Street Chicago, IL, 60637-1573 phone 773-702-3234 (lab) fax 773-702-9740 http://home.uchicago.edu/~harr/ ---------------------------------------------------------------------