Another change you might notice in MDT 2012 Update 1 is that Lite Touch deployments never use SETUP.EXE.  That doesn’t result in any real change in functionality, as we still do the equivalent steps:

  • Applying the image using ImageX.exe.
  • Servicing the image using DISM, which injects drivers, software updates, language packs, etc.
  • Creating a BCD entry to boot the operating system using BCDBoot.exe.

So then the question becomes “why”.  Well, there are a few reasons:

  • Running Windows 7’s SETUP.EXE doesn’t quite work when using Windows PE 4.0 from the Windows 8 Assessment and Deployment Kit (ADK).
  • Some complex multiple disk scenarios (more common on servers) could result in errors during installation; similar errors don’t happen when using ImageX.
  • It’s no longer necessary to use SETUP.EXE.  With Windows Vista and its INSTALL.WIM, you couldn’t apply the WIM directly because the drive letter of the image (D:) was different from the drive letter of the machine (C:).
  • It’s a little faster Smile

So does that mean you never need to import full operating system files?  Not quite.  They are still needed in these situations:

  • When installing Windows XP or Windows Server 2003 from source files.
  • When installing Windows Vista or Window Server 2008 from the original source files (using INSTALL.WIM), because of the drive letter change issue described above.
  • When adding the .NET 3.5 feature to a Windows 8 or Windows Server 2012 installation (more on that in a later blog).

In MDT 2012, we used SETUP.EXE as the primary installation method, but would fall back to ImageX if SETUP.EXE wasn’t available.  Now with MDT 2012 Update 1, the default is to use ImageX.

p.s.  ConfigMgr 2012 SP1 will also prefer using image packages instead of install packages for the same basic reasons.