title: Installer waiting when EXE is run as custom action during installation
body: <p>I am installing Mosquitto using WIX and once the files are copied I'm trying to run the mosquitto.exe using a custom action. It launches a new command prompt and the installation pauses there. It resumes only when I terminate that command prompt. Below is my code.</p>
  
  <pre><code>&lt;Feature Id="ProductFeature" Title="MosquittoInstaller" Level="1"&gt;
    &lt;ComponentGroupRef Id="MosquittoFilesGroup"/&gt;
      &lt;/Feature&gt;
  &lt;InstallExecuteSequence&gt;
    &lt;Custom Action="RunMosquitto" Before="InstallFinalize" /&gt;
  &lt;/InstallExecuteSequence&gt;
  
  
    &lt;Directory Id="TARGETDIR" Name="SourceDir"&gt;
    &lt;Directory Id="INSTALLLOCATION"&gt;
      &lt;Directory Id="KubeInstallDir" Name="Kube2.0"&gt;
        &lt;Directory Id="MyProgramDir" Name="Mosquitto" /&gt;
      &lt;/Directory&gt;
    &lt;/Directory&gt;
  &lt;/Directory&gt;
  &lt;CustomAction Id='RunMosquitto'  FileKey="fil7D28AEF774656849395A2FA20A5C963D"  Execute="deferred" ExeCommand='-v' Return="check" HideTarget="no" Impersonate="no"/&gt;
  </code></pre>
  
  <p>What am I doing wrong here? Please advice.</p>