title: dpinst fails to install driver silently
body: <p>I use Inno Setup installer to install my Win32 application, it is installed mainly on Windows 10. There is a driver for some USB dongle (basically it is USB serial port) to be installed together with my app. The driver consists of files and directories:</p>
  
  <pre><code>amd64 (folder)
  x86 (folder)
  dfu.cat
  dfu.inf
  usbserial.cat
  usbserial.inf
  </code></pre>
  
  <p>I added <code>dpinst32.exe</code> and <code>dpinst64.exe</code> to the driver's folder and I call <code>dpinst32</code> or <code>dpinst64</code> (based on Windows version) from my installer.</p>
  
  <p>However, on some PCs I end with drivers not installed.</p>
  
  <p>What is the correct way to install drivers by my installer?</p>
  
  <p>EDIT: This is log from <code>dpinst64.exe /Q /c</code></p>
  
  <pre><code>INFO:   Option set: dumping log info to console.
  INFO:   Current working directory: 'F:\windrv'
  INFO:   Running on path 'F:\windrv'
  INFO:   No valid 'dpinst.xml' file provided.
  INFO:   Install option set: Running in quiet mode. Suppressing Wizard and OS popups.
  INFO:   Found driver package: 'F:\windrv\dfu.inf'.
  INFO:   Found driver package: 'F:\windrv\usbserial.inf'.
  INFO:   Preinstalling 'f:\windrv\dfu.inf' ...
  INFO:   ENTER:  DriverPackagePreinstallW
  INFO:   RETURN: DriverPackagePreinstallW  (0xE0000242)
  INFO:   Preinstalling 'f:\windrv\usbserial.inf' ...
  INFO:   ENTER:  DriverPackagePreinstallW
  INFO:   RETURN: DriverPackagePreinstallW  (0xE0000242)
  INFO:   Returning with code 0x80020000
  </code></pre>