Error in namespaceExport(ns, exports) : undefined exports: … Error: package or namespace load failed

Question

I recently updated R to the latest version (R version 3.1.1) and now I can´t run load packages. In the case of ggplot2, the error message after running library(\"ggplot2\") is

Answer 1

Indeed, one or more of the dependend packages had to be updated.

I created a new empty library directory where I re-installed all packages and this solved the problem. Thanks!

My error was updating only ggplot2 update.packages("ggplot2") while I should have ran update.packages().