title: Cannot knit .rmd file into PDF, HTML or Word
body: <p>My OS is MacOS Catalina. 
  RStudio Version- 1.2.5 </p>
  
  <p>The trouble is with knitting R Markdown document to PDF, HTML or Word. Whenever I press "knit" I get the following error: </p>
  
  <pre><code>Error in loadNamespace(i, c(lib.loc, .libPaths()), versionCheck = vI[[i]]) : 
    object 'vI' not found
  Calls: :: ... asNamespace -&gt; loadNamespace -&gt; namespaceImport -&gt; loadNamespace
  Execution halted
  </code></pre>
  
  <p>I have downloaded latest version of MacTex as well but still it doesn't seem to solve the problem. 
  I've also installed important packages- rmarkdown, rcpp, knitr among others.</p>
  
  <p>Please help! I'll be grateful if you can</p>