title: Vendor folder does not exist and cannot be created
body: <p><strong>Question:</strong></p>
  
  <p>What kind of permissions should I give to Composer on Windows?</p>
  
  <p><strong>Server information:</strong></p>
  
  <ul>
  <li><p>Windows 2012 R2</p></li>
  <li><p>IIS 8.5</p></li>
  </ul>
  
  <p><strong>Error message:</strong></p>
  
  <p>[RuntimeException]</p>
  
  <p>C:\inetpub\wwwroot/vendor does not exist and could not be created.</p>
  
  <p><strong>Steps that I've tried and thoughts:</strong></p>
  
  <p>I've installed Composer through the .exe file.</p>
  
  <p>I have a composer.json file in C:\inetpub\wwwroot and when I try running <code>composer install</code> or <code>composer update</code>, I get the error message.</p>
  
  <p>I've tried manually creating the vendor folder in the directory, but then it cannot download the package that I have in my composer.json file, giving roughly the same error message, that the package doesn't exist and could not be created.</p>
  
  <p>I've googled the error, and I'm led to believe it's a permissions issue, however, I have installed Composer on another server and installed packages in the C:\inetpub\wwwroot directory without a problem. I've tried comparing security group permissions between the two servers for wwwroot and inetpub, and the permissions were the same. I had someone suggest trying to copy the .json file to My Documents on the server and try running composer install from there, and that worked. Which further indicates it's a permissions issue, but I can't figure out what.</p>