User`s manual

DA-683 XPE User's Manual Software Configuration
File Based Write Filter
File-Based Write Filter (FBWF) allows Windows Embedded Standard 2009 to maintain the appearance of read
and write access to write sensitive or read only storage. FBWF makes read and write access transparent to
applications.
Writing to storage media may be undesirable or impossible in embedded devices. FBWF redirects all writes
targeted for protected volumes to a RAM cache called an overlay. In this context, an overlay can be likened to
a transparency overlay on an overhead projector. Any change made to the overlay affects the picture as seen
in the aggregate, but if the overlay is removed, the underlying picture remains unchanged.
Follow the steps below to enable FBWF:
1. In the command prompt, type fbwfmgr /displayconfig to check the current FBWF status. The status
defaults to disabled.
C:\>fbwfmgr /displayconfig
File-based write filter configuration for the current session:
Filter state: disabled.
File-based write filter configuration for the next session:
Filter state: disabled.
C:\>
2. Type fbwfmgr /enable to enable FBWF. Reboot the system for the changes to come into effect.
C:\>fbwfmgr /enable
File-based write filter will be enabled on the next reboot.
C:\>
3. When the system has rebooted, type fbwfmgr /displayconfig in the command prompt again to confirm
thatthe status has been changed to enabled. The default folder for FBWF will be \temp. Type fbwfmgr
/help for more detailed information.
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