Dear All, I have a very simple question to which I did not find any answer online (apologize if it exists). I have an XML file (attached) on which I just want to modify the info of a node. So, I load my xml file: current = xmlTreeParse(file, useInternalNodes=T) and I want to change the information of: <filename>1.jpg</filename> to be, for example: 1-1.jpg (newname) I do: xmlValue( xpathApply( current, "/annotation/filename")[[1]] ) = newname now, the crazy thing is that it does the change to the xml but it also through the following error: Error in xmlValue(xpathApply(current, "/annotation/filename")[[1]]) = newname : could not find function "xpathApply<-" it seems that it works, but for a mysterious reason, it also seems that it does not work. Since I have to apply this change many times, and write the resulting modified .xmls, the loop would stop as a result of the error... what am i missing here? is there any simpler way to do it? thanks a lot for your kind help, Moreno P.S. I also try: xmlSApply(xpathApply( current, "/annotation/filename")[[1]], xmlValue) = newname obtaining the same result. -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.