title: Installing R library XLConnect on OS 10.8.2
body: <p><a href="http://cran.r-project.org/web/packages/XLConnect/index.html" rel="noreferrer">XLConnect</a> is, as the manual describes it, "a package that allows for reading, writing and manipulation of Microsoft Excel files from within R".</p>
  
  <p>Installation on Windows and Linux is straightforward. Simply tell R to <code>install.packages("XLConnect")</code>, and you're done. On OS X you need to use <code>install.packages("XLConnect", type="source")</code>, the installation instructions say.</p>
  
  <p>Trying this under OS 10.8.2, R output a number of error messages. I post them here, so Google can send people with similar problems to this Q and A. For a solution to the problem, scroll down.</p>
  
  <hr>
  
  <p>R output:</p>
  
  <pre><code>&gt; install.packages("XLConnect", type = "source")
  also installing the dependencies ‘XLConnectJars’, ‘rJava’
  
  versuche URL 'http://ftp5.gwdg.de/pub/misc/cran/src/contrib/XLConnectJars_0.2-4.tar.gz'
  Content type 'application/x-gzip' length 16539227 bytes (15.8 Mb)
  URL geöffnet
  ==================================================
  downloaded 15.8 Mb
  
  versuche URL 'http://ftp5.gwdg.de/pub/misc/cran/src/contrib/rJava_0.9-3.tar.gz'
  Content type 'application/x-gzip' length 537153 bytes (524 Kb)
  URL geöffnet
  ==================================================
  downloaded 524 Kb
  
  versuche URL 'http://ftp5.gwdg.de/pub/misc/cran/src/contrib/XLConnect_0.2-4.tar.gz'
  Content type 'application/x-gzip' length 1719698 bytes (1.6 Mb)
  URL geöffnet
  ==================================================
  downloaded 1.6 Mb
  
  * installing *source* package ‘rJava’ ...
  ** Paket ‘rJava’ erfolgreich entpackt und MD5 Summen überprüft
  /Library/Frameworks/R.framework/Resources/bin/config: line 142: make: command not found
  /Library/Frameworks/R.framework/Resources/bin/config: line 143: make: command not found
  /Library/Frameworks/R.framework/Resources/bin/config: line 219: make: command not found
  /Library/Frameworks/R.framework/Resources/bin/config: line 142: make: command not found
  /Library/Frameworks/R.framework/Resources/bin/config: line 143: make: command not found
  /Library/Frameworks/R.framework/Resources/bin/config: line 219: make: command not found
  checking for gcc... no
  checking for cc... no
  checking for cl.exe... no
  configure: error: no acceptable C compiler found in $PATH
  See `config.log' for more details.
  ERROR: configuration failed for package ‘rJava’
  * removing ‘/Library/Frameworks/R.framework/Versions/2.15/Resources/library/rJava’
  ERROR: dependency ‘rJava’ is not available for package ‘XLConnectJars’
  * removing ‘/Library/Frameworks/R.framework/Versions/2.15/Resources/library/XLConnectJars’
  ERROR: dependencies ‘XLConnectJars’, ‘rJava’ are not available for package ‘XLConnect’
  * removing ‘/Library/Frameworks/R.framework/Versions/2.15/Resources/library/XLConnect’
  
  Die heruntergeladenen Quellpakete sind in 
      ‘/private/var/folders/some/path/to/downloaded_packages’
  Warnmeldungen:
  1: In install.packages("XLConnect", type = "source") :
   Installation des Pakets ‘rJava’ hatte Exit-Status ungleich 0
  2: In install.packages("XLConnect", type = "source") :
   Installation des Pakets ‘XLConnectJars’ hatte Exit-Status ungleich 0
  3: In install.packages("XLConnect", type = "source") :
   Installation des Pakets ‘XLConnect’ hatte Exit-Status ungleich 0
  &gt; library(XLConnect)
  Fehler in library(XLConnect) : es gibt kein Paket namens ‘XLConnect’
  </code></pre>