Moxa V2403-C3-W-T [22/63] V2403 series windows software enabling embedded filters

V2403 Series Windows Software Enabling Embedded Filters

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File-Based Write Filter

This section describes how to use the File-Based Writer Filter (FBWF). Note that when Enhanced Writer Filter is

enabled, the File-Based Writer Filter function will not work.

According to Microsoft:

“File-Based Write Filter (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. Used in this context, 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.”

FBWF supports an advanced ESF feature, which allows users to specify which directory to write data to. The

default directory is c:\temp. The advanced feature allows you can read/write data to disk without committing

an action.

Configuring File-Based Write Filter

Complete the following steps to enable the File-Based Write Filter (FBWF) feature. Although you can enable

FBWF and EWF on the same computer, FBWF does not protect a volume that is already protected by EWF.

Similarly, EWF does not protect a volume that is already protected by FBWF.

NOTE

Before using FBWF,

make sure that you disable EWF.

1. Double-click the padlock icon in the system tray.

You may need to show hidden icons in the system tray.

NOTE

When disabled, the EWF and FBWF icons in the system tray look the same. To verify that you have opened the

correct writer filter program, check the screen title.