title: Installing RMarkdown packages in RStudio does not work on Windows 7
body: <p>I have installed RStudio 0.98 on Windows 7 64bit and when I try to create a new RMarkdown script for the first time, it asks me to install RMarkdown (packages or something). </p>
  
  <p>When I confirm this, the process fails, throwing the following error(s):</p>
  
  <pre><code>Installing package into 'C:/Users/grosseti/AppData/Roaming/R'
  (as 'lib' is unspecified)
  Der Befehl "C:\Program" ist entweder falsch geschrieben oder
  konnte nicht gefunden werden.
  Warning messages:
  1: running command '"C:/Program Files/R/R-3.1.2/bin/x64/R" CMD INSTALL -l "C:\Users\grosseti\AppData\Roaming\R" "C:/Program Files/RStudio/R/packages/rmarkdown_0.3.10_b96214b9ac86b437067a0aa21442203f52face83.tar.gz"' had status 1 
  2: In utils::install.packages("C:/Program Files/RStudio/R/packages/rmarkdown_0.3.10_b96214b9ac86b437067a0aa21442203f52face83.tar.gz",  :
    installation of package 'C:/Program Files/RStudio/R/packages/rmarkdown_0.3.10_b96214b9ac86b437067a0aa21442203f52face83.tar.gz' had non-zero exit status
  </code></pre>
  
  <p>The German sentence</p>
  
  <pre><code>Der Befehl "C:\Program" ist entweder falsch geschrieben oder
  konnte nicht gefunden werden.
  </code></pre>
  
  <p>basically means that the "command C:\Program is either wrongly spelled or cannot be found". </p>
  
  <p>I am pretty sure that it has something to do with escaping, as there is a whitespace in C:\Program Files.</p>
  
  <p>But what do I know, shouldn't this just work? Also notice that there are sometimes <code>/</code> in use, sometimes <code>\</code>. </p>
  
  <p>Output of <code>.libPaths()</code>: </p>
  
  <pre><code>[1] "C:/Users/grosseti/AppData/Roaming/R" "C:/Program Files/R/R-3.1.2/library" 
  </code></pre>
  
  <p>(Hint: I set the "C:/Users/grosseti/AppData.." path manually in <code>RProfile.site</code>.)</p>
  
  <p>Where do I start???</p>