[BioC] Installation failed

[Jeff Gentry]

> Loading required package: widgetTools 
> Error in firstlib(which.lib.loc, package) : 
>         TCL_LIBRARY is not set
> Error in firstlib(which.lib.loc, package) : 
>         Package tcltk unavailable!
> Error in eval(expr, envir, enclos) : Package widgetTools unavailable
> Error in firstlib(which.lib.loc, package) : 
>         Need package methods
> Error in library(reposTools) : .First.lib failed

As it says, your TCL_LIBRARY variable is not set properly, thus your R is
misconfigured.

Please see the R Windows FAQ at www.r-project.org (question 3.6)