Moxa DA-682A-C7-DPP [14/36] Fbwfmgr displayconfig

DA-682A-DPP Windows Software Enabling Windows 7 Write Protections

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File-Based Write Filter

Overview

The File-Based Write Filter (FBWF) is similar to Enhanced Write Filter (EWF), but is enforced at the file level

rather than at the hardware (bit) level. Compared to the EWF, the File-Based Write Filter is less secure, but

provides more features.

FBWF allows the Windows Embedded platform to maintain the appearance of read and write access on

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. An overlay is similar 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.

One of FBWF’s advanced features allows the user to specify a directory in the data drive to which the data can

be written, which is not possible in the case of EWF.

Enabling File-Based Write Filter

To enable file-based write filtering, do the following:

1. Check the current status of the Enhanced Write Filter using the

C:\...\>fbwfmgr /displayconfig

command.

2. Type

fbwfmgr /enable at the command prompt to enable the FBWF. Reboot the system for the changes

to take effect.