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How To Manage Enhanced Write Filter Function Within XP Embedded

Why is the EWF function needed?

Using the EWF without committing the writes has many advantages when used for an IPC with XP Embedded. In this configuration the system works like a ROM based system. Every time when the IPC is boot up it will be with a clean XP Embedded system. Unlike a ROM based system XP Embedded can still be updated if required through a special 'commit command'. In conclusion XP Embedded in combination with the EWF function can make the IPC more reliable.

Checking the status of the EWF function:

To check the status of the EWF function, you can run a command, however this will fail if there is no space available on the disk for the EWF partition.  See below how to handle this.

Display the command prompt screen, and then put in the following command to confirm the operating state of the EWF function.
Command: ewfmgr c:

Execution Example:

Definition state:
Enabled – Indicates that the EWF function is enabled. This state will emulate writing to the drive.

Disabled – Indicates that the EWF function is disabled. In this state all writes will be written direct to the drive.

If this command gives an error message, check using 'Disk Management' that there is unallocated space for EWF information (some DyaloX images are designed to fill the disk - 4GB, 8GB or 16GB).  Check by going to computer management - you need to right click on 'My Computer' -> Manage -> The navigate down to 'Disk Management':

If there is a small 'Unknown' partition at the top of the list - it needs to be deleted. Right click on the partition and choose 'Delete Partition':

You must now reboot in order to use ewfmgr.

IMPORTANT: Do NOT delete C: or D: partitions, you will lose data and need to re-image your DyaloX


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Created 2010-07-29
Modified 2013-07-26
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