[O] Executable not found error with begin_src R but not begin_src R :session on Windows

[John Hendy]

On 8.0-pre and have never had an issue with R source code blocks
before. I was just trying something simple like:

#+begin_src R :exports results

a <- 1+2
a

#+end_src

I got empty #+results block upon execution and the *Org Babel Error*
(something like that) buffer had an error about the executable not
being found. Adding =:session= produced results, though.

Is there something new about the difference between execution with and
without sessions with R?


John