library(caret)
Error in loadNamespace(j <- i[[1L]], c(lib.loc, .libPaths()), versionCheck = vI[[j]]) : namespace ‘nlme’ 3.1-121 is already loaded, but >= 3.1.123 is required
In addition: Warning message: package ‘caret’ was built under R version 3.2.4 Error: package or namespace load failed for ‘caret’