Redeploying an EWF-Protected Run-Time Image to New Media

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If you decide to redeploy your run-time image onto differently sized media, or onto media with different partition configurations, you can reinitialize the EWF volume. Because the EWF volume stores configuration information about the volume sizes, you must reinitialize the EWF volume when you redeploy your run-time image onto differently sized media.

To redeploy an EWF-protected run-time image to new media

  1. Add the following registry keys to your run-time image. You can use regedit, create a component that adds these values, or add these as extra resources in your configuration. For more information, see Adding Registry Data to a Configuration in Windows XP Embedded Studio Help.

    Key Name: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ewf\Parameters\Overlay
    Value Name: ArcName
    Type: REG_SZ
    Value: multi(0)disk(0)rdisk(0)partition(2)

    Set the data value to the correct boot Arc path of the EWF partition. For more information about Boot Arc paths, see Multiple-Boot System.

    Key Name: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ewf\Parameters\Protected\Volume0
    Value Name: Enabled
    Type: REG_DWORD
    Value: 00000000

    Set the data value to 0 to disable EWF, or set it to 1 to enable EWF.

  2. Zero out the first 4 bytes of the EWF volume.

  3. Partition your new media as required, and deploy your run-time image onto the new media.

  4. Boot from the target media. EWF starts disabled, and you can make any additional changes to your run-time image, including installing applications or other updates.

    When the system boots, EWF will fail to find the EWF partition signature because the first 4 bytes of the EWF partition have been zeroed out. EWF checks the registry for the Arc Name value and initializes the EWF partition. The Enabled value is copied to the EWF partition, and the system continues to boot with EWF disabled.

  5. Use the EWF Manager command enable to enable EWF the next time the system starts:

    ewfmgr c: -enable

    Or, issue an EwfMgrEnable command programmatically by using the EWF API.

See Also

Enhanced Write Filter | Troubleshooting Enhanced Write Filter

Last updated on Wednesday, October 18, 2006

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