High Quality Content by WIKIPEDIA articles! Enhanced Write Filter (or EWF) is a component of Windows XP Embedded which filters writes to another medium instead of being physically written to the volume itself. EWF allows the writes to be discarded or committed to the physical volume later (either directly or through inaction based on the configuration). As this minimizes writes to a specified hard disk, EWF and FBWF (File-Based Write Filter) have become popular in enthusiast computing as a way to decrease wear of Solid State Drives on NetBooks and CarPC`s.