title: readRDS(file) in R
body: <p>Whenever I try to install a package in R, I get the following error:</p>
  
  <pre><code>Error in readRDS(file) : unknown input format
  </code></pre>
  
  <p>This just started occurring after I had a system crash.  I am running 32 bit R 2.13.0 under windows 7.  I tried removing and re-installing R, but continue to get the error.  Is there any way I can fix this without deleting everything (i.e. all the packages I've installed) and starting over?</p>
  
  <p>Thanks</p>