Windows Embedded 8 Standard for HP Thin Clients - Administrator Guide

3 Unified Write Filter
Unified Write Filter (UWF) provides a secure environment and can extend the life of a thin client by
protecting it from unauthorized and excessive writes to the flash drive. Write data is intercepted by
UWF and cached in the RAM drive, and as a result, lost after the next thin client restart.
UWF allows you to specify files, directories, and registry keys to be excluded from protection.
Excluded items will always write to the underlying volume.
For an overview of the different ways to manage UWF, see
Write filter management overview
on page 5.
For information about how to make permanent changes to the system, see
Configuring UWF to allow
permanent changes on page 7.
For information about how to cancel a UWF action previously assigned to take place on the next thin
client restart, see
Clearing the boot command on page 8.
CAUTION: Ensure that the write filter is enabled after committing necessary configurations to the
thin client flash drive. During normal operation of the thin client, the write filter must be enabled. Also
ensure that Page File is not enabled on thin clients with flash memory storage. Failure to follow these
required actions can void the warranty of the flash storage device. In the event of damage to the flash
storage device due to operation with a disabled write filter or enabled Page File, the damage will not
be covered by HP warranty.
4 Chapter 3 Unified Write Filter