I just loaded (onto XP pro) and tried to use v1.7.1 (been using 1.6.1) and get the following new error when I call read.marrayInfo (with the same files that work on 1.6.1): (e.g. targets<-read.marrayInfo(fname="details.txt",labels=2) where details.txt is in the current dir) Error in validObject(.Object) : Invalid "marrayInfo" object: Invalid object for slot "maInfo" in class "marrayInfo": got class "NULL", should be or extend class "data.frame" can anyone help me fix this? I have no idea why this function no longer works... Thanks, Lily Lily Shiue Center for Biomolecular Science and Engineering 225 Sinsheimer Labs University of California Santa Cruz, CA 95064 Tel: (831) 459-2612 Fax: (831) 459-3139 lshiue@soe.ucsc.edu