I've recently had a series of similar errors trying to install packages to R 2.1.1 running under Windows XP. > utils:::menuInstallLocal() package 'randomForest' successfully unpacked and MD5 sums checked updating HTML package descriptions Warning message: unable to move temporary installation 'C:\Program Files\R\rw2011\library\file25214\randomForest' to 'C:\PROGRA~1\R\rw2011\library\randomForest' > I get the same error if I try directly installing from CRAN or from a local zip file. I've fixed it for some earlier package downloads by reinstalling R and packages, but I don't want to have to do that every time. Any ideas about what the problem is? Many thanks, John Field =========================John Field Consulting Pty Ltd 10 High St, Burnside SA 5066 ph: (08) 8332 5294 or 0409 097 586 fax: (08) 8332 1229 email: JohnField at ozemail.com.au