Compiling RInside programs on Windows [duplicate]

Answer 1

It fails because you installed R in C:\Program Files\R even though the FAQ for R on Windows tells you not to install R in a path with spaces. See "Question 2.2: How do I install R for Windows":

If you want to be able to build packages from sources, we recommend that you choose an installation path not containing spaces.

The Rcpp / RInside documentaion repeats that recommendation. Do not install R in a path with spaces. If you must, you have to fix the Makefile to avoid the path expansion from breaking.

Answer 2

Your path are totally wrong for me: why you use C:\R\Rtools\bin as R_HOME if your R main path is simply C:\R ? If your R folder is what you've shown in the screenshot, BTW, also your classpath is totally wrong!