title: MSI installer calling another MSI installer in silent mode using WiX
body: <p>I'm using <a href="http://en.wikipedia.org/wiki/WiX">WiX</a> to make an <a href="http://en.wikipedia.org/wiki/Windows_Installer">MSI</a> installer to call another MSI installer.</p>
  
  <ul>
  <li>I can resolve this situation in UILevel=5 (Full UI) mode. My solution is add a CustomAction to the UISequence table that call another MSI. It will not get error code 1500: "Another installation is already in progress..."</li>
  <li>But in slient mode, UILevel = 2, I can't do it, because it only runs CustomAction in ExecuteSequence.
  How can I run my MSI in silent mode and call another MSI installer?</li>
  </ul>