Hi, I installed the newest R version 2.6.2. and the newest biomaRt version biomaRt_1.12.2 I got the following error. Would someone please tell me what wrong with this package? package 'RCurl' successfully unpacked and MD5 sums checked package 'XML' successfully unpacked and MD5 sums checked The downloaded packages are in C:\Users\swang.UNCSPH\AppData\Local\Temp\RtmpJjs9mF\downloaded_packages updating HTML package descriptions > library(biomaRt) Loading required package: RCurl > ensembl = useMart("ensembl") Error in .Call("RS_XML_ParseTree", as.character(file), handlers, as.logical(ignoreBlanks), : error in creating parser for > listMarts() Error in .Call("RS_XML_ParseTree", as.character(file), handlers, as.logical(ignoreBlanks), : error in creating parser for > sessionInfo() R version 2.6.2 (2008-02-08) 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] stats graphics grDevices utils datasets methods base other attached packages: [1] biomaRt_1.12.2 RCurl_0.8-1 loaded via a namespace (and not attached): [1] tools_2.6.2 XML_1.7-3 Thanks Shiliang [[alternative HTML version deleted]]