title: Cannot reinstall PostgreSQL because Windows thinks it's still installed
body: <p>I've installed PostgreSQL but I want to reinstall it to another directory. So I've uninstalled it and when I execute the installer I get:</p>
  
  <blockquote>
    <p>An existing PostgreSQL installation has been found at C:\Program Files (x86)\PostgreSQL\9.1. This installation will be upgraded.</p>
  </blockquote>
  
  <p>I'll add that I didn't uninstall PostgreSQL with Add/Remove programs from Control Panel because I was getting an error in French so I just removed the main directory and then removed it from Control Panel.</p>
  
  <p>I've also removed <code>HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\postgresql-9.1</code> and WampServer which used PostgreSQL (just in case). I cannot find any other keys in regedit because the search is taking forever (and I think it's bugged). And I got rid of the directories <code>C:\Users\&lt;username&gt;\AppData\Roaming\postgresql</code> and <code>C:\USers\postgresql</code>.</p>
  
  <p>Perhaps it has something to do with Visual Studio because when I run the installer I briefly get a window:
  <a href="https://i.stack.imgur.com/ARXzs.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ARXzs.png" alt="enter image description here"></a></p>