title: WIX installation directory not customizable?
body: <p>I'm using WIX 3.5 for my setup project. If I change the installation directory during installation, the installer insists on using the default directory.</p>
  
  <pre><code>&lt;Directory Id="TARGETDIR" Name="SourceDir"&gt;
    &lt;Directory Id="LocalAppDataFolder" Name="AppData"&gt;
      &lt;Directory Id="InstallationDir" Name="MyApp" /&gt;
    &lt;/Directory&gt;
  &lt;/Directory&gt;
  ...
  &lt;DirectoryRef Id="InstallationDir"&gt;
     ... component + files ...
  &lt;/DirectoryRef&gt;
  ...
  &lt;UI&gt;
     &lt;Property Id="WIXUI_INSTALLDIR" Value="InstallationDir" /&gt;
     &lt;UIRef Id="WixUI_InstallDir" /&gt;
     &lt;UIRef Id="WixUI_ErrorProgressText" /&gt;
  &lt;/UI&gt;
  
  &lt;CustomAction Id="SetARPINSTALLLOCATION" Property="ARPINSTALLLOCATION" Value="InstallationDir" /&gt;
  &lt;InstallExecuteSequence&gt;
     &lt;Custom Action="SetARPINSTALLLOCATION" After="InstallValidate" /&gt;
  &lt;/InstallExecuteSequence&gt;
  </code></pre>
  
  <p>I tried both upgrading (I'm always changing the product code) and uninstall/install. Same problem!
  If I run <code>msiexec /L*v log.txt /i Setup.msi</code> the log tells me that the <code>InstallationDir</code> property was indeed changed.</p>
  
  <p><strong>Q:</strong> How is it possible that my software is installed into the default directory?</p>