title: Error after running build() to create R package in RStudio
body: <p>I am trying to build an R package using RStudio on Windows 8 Pro. When I attempt to build the package by running <code>build()</code> I get the error:</p>
  
  <pre><code>"C:/Program Files/R/R-30~1.2/bin/x64/R" --vanilla CMD build "H:\File Assembly\FileAssembler"  \
  --no-manual --no-resave-data 
  
  'C:\Program' is not recognized as an internal or external command, operable program or batch file.
  Error: Command failed (1)
  </code></pre>
  
  <p>I already have <code>MiKTEX</code> installed and I have checked this by:</p>
  
  <pre><code>Sys.which("pdflatex") 
                                                          pdflatex
  "C:\\Program Files (x86)\\MIKTEX~1.9\\miktex\\bin\\pdflatex.exe" 
  </code></pre>
  
  <p>The R version I am using is: <code>R version 3.0.2 (2013-09-25) -- "Frisbee Sailing"</code></p>
  
  <p>Loading library(devtools) and running find_rtools(T) gives:</p>
  
  <pre><code>find_rtools(T)  
  Scanning path...
  ls : c:\Rtools\bin\ls.exe 
  gcc: c:\Rtools\GCC-46~1.3\bin\gcc.exe 
  VERSION.txt
  Rtools version 3.1.0.1942 
  Version: 3.1 
  [1] TRUE
  </code></pre>
  
  <p>In addition, the path for <code>rtools</code> exes are:</p>
  
  <pre><code>Sys.which("ls.exe")
                     ls.exe 
  "c:\\Rtools\\bin\\ls.exe" 
  
  Sys.which("gcc.exe")
                                 gcc.exe 
  "c:\\Rtools\\GCC-46~1.3\\bin\\gcc.exe" 
  </code></pre>
  
  <p>And checking the path in R:</p>
  
  <pre><code>Sys.getenv('PATH')
  [1] "C:\\Program Files\\R\\R-3.0.2\\bin\\x64;c:\\Rtools\\bin;c:\\Rtools\\gcc-4.6.3\\bin;……other paths…………;C:\\Program Files (x86)\\MiKTeX 2.9\\miktex\\bin\\"
  </code></pre>
  
  <p>I would really appreciate help with identifying what I have missed out.</p>