Hi: I am running the following code to query Pubmed database, but getting the error "couldn't connect to host". library(RCurl) library(XML) library(tm) url <- "http://eutils.ncbi.nlm.nih.gov/entrez/eutils/esearch.fcgi?" q <- "db=pubmed&term=saunders+nf[au]&usehistory=y" esearch <- xmlTreeParse(getURL(paste(url, q, sep="")), useInternal = T) Error in function (type, msg, asError = TRUE) : couldn't connect to host How can this problem be solved? Thanks: John