While in-place upgrades are nice, there are quite a few scenarios when you need to use the old-school deployment scenarios (new computer, refresh computer and replace compute).

Update September 25, 2016: Windows 10 v1607 added in additional support for third party disk encryption.

The Windows 10 Setup Upgrade process

When using the /Auto Upgrade switch to upgrade Windows 7/8/8.1 to Windows 10 (which migrates data, settings and apps) it does NOT support the following:

• Use a custom reference image
• Change from BIOS to UEFI or do other disk layout changes (change partitioning)
• Upgrade when having third party disk encryption (for now, may change depending on vendor)
   
• Note: In Windows 10 v1607 (and later), the new /ReflectDrivers setup switch allows inplace-upgrade when using third party disk encryption
• Upgrade when third party antivirus software installed (for now, may change depending on vendor)
• Upgrade between architecture (e.g. x86 to x64)
• Change the language (base OS language)    
• Change to a lower SKU (the /Auto:Upgrade can only upgrade to the same or higher SKUs)
• Upgrade a "boot from VHD" system
• Upgrade Windows To Go USB sticks

/ Johan

Happy deployment, and thanks for reading! / The Deployment Research team For any questions / comments to this post, use our Facebook page: https://www.facebook.com/DeploymentResearch Also, please subscribe to the Deployment Artist YouTube channel: https://www.youtube.com/user/DeploymentArtist
		Ami Casto Follow Ami on Twitter: @mdtpro If you want to connect to Ami via LinkedIn: https://www.linkedin.com/in/ami-casto				Johan Arwidmark Follow Johan on Twitter: @jarwidmark If you want to connect to Johan via LinkedIn: https://www.linkedin.com/in/jarwidmark