Omron NYB17-11, User Manual

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A-2 Customize Windows
This section provides an overview of the tools to customize Windows.
A-2-1
Enhanced Write Filter
The Enhanced Write Filter (EWF) is applicable to Box PCs with a Windows 7 operating system.
The Enhanced Write Filter (EWF) intercepts disk changes and stores them into a memory overlay in
RAM memory instead of applying them to the original volume.
Additional Information
• File-Based Write Filter (FBWF) provides a similar function, but operates at the file level, while
EWF operates at the sector level.
• Refer to the Microsoft Developer Network (MSDN) for detailed information.
Application
EWF and FBWF provide the following benefits:
• Write-protect one or more partitions on a system.
• Make it possible to revert changes and revert to the original disk content.
• Enable booting from read-only media.
By redirecting all write requests to RAM, EWF and FBWF enable the run-time image to maintain the
appearance of a writable run-time image.
• Improve the file system performance when using relatively slow storage.
• Minimize write actions to the disk.
For example, minimize write access to flash memory. Write cycles on flash memory are limited for
technical reasons.
Usage
EWF is included in the Windows Embedded Standard 7 image and disabled by default. The configura-
tion of this component can be defined with the command line tool
EWFMGR.EXE
.
To run to EWF Manager, open the Command Prompt with Administrator rights.
Command Function Remarks
ewfmgr
Shows an overview with current
status. ---
ewfmgr c: -enable
Enables the write filter for the drive
C:. The protection is not effective until
the system is restarted.
ewfmgr c: -commit
Writes all the changes in the mem-
ory overlay to the physical disk dur-
ing the next restart. Committing the overlay can affect
the speed of the boot process.
ewfmgr c: -commitanddisable
Writes all the changes in the mem-
ory overlay to the physical disk dur-
ing the next restart, and disables
the disk protection. Committing the overlay can affect
the speed of the boot process.
The protection is not disabled until
the system is restarted.
Appendices
A - 11
NY-series Industrial Box PC User's Manual (W553)
A-2 Customize W
indows
A
A-2-1 Enhanced W
rite Filter