This article discusses the following scenarios:
- Install Windows to USB drive.
- Install Windows to Flash Drive(UFD) drive.
- Install Windows to ESATA drive.
- Store Windows 7 Native Boot VHD on USB/UFD drive.
It is unsupported to boot Windows from external devices. Some of the reasons why this is not supported:
- Potential Boot Path support issues.
- Activation issues.
- You must disable the device write cache or click ‘safe removal’ before unplugging the cable. Otherwise, there could be a data loss.
Some specialized products do support this type of scenario:
- Windows 7 embedded: http://www.microsoft.com/windowsembedded/en-us/products/westandard/default.mspx
- Deploying Microsoft Hyper-V Server 2008 R2 on USB Flash Drive: http://technet.microsoft.com/en-us/library/ee731893(WS.10).aspx
Note: Booting Hyper-V Server 2008 R2 from USB flash drive is only supported for OEM's.