This function sets the persistent data for an Enhanced Write Filter (EWF)-protected volume. Persistent data (32 bytes per protected volume) is retained through all EWF operations, including disable, enable, and restore operations.

BOOL EwfMgrSetPeristentData(
  HANDLE hDevice,
  LPBYTE lpPersistentData,
  DWORD cbPersistentData


[in] Handle to the EWF-protected volume.
[in] Long pointer to a buffer that contains the persistent data to save.
[in] Specifies the size, in bytes, of the buffer pointed to by lpPersistentData. Only the first 32 bytes (EWF_MAX_PERSISTENT_DATA) are saved.

Return Values

If the function succeeds, the return value is TRUE. If the function fails, the return value is FALSE. Call GetLastError for extended error information.


This function is supported on both disk and RAM overlays with an associated EWF overlay store tracking its protection settings. However, it is not supported on RAM overlays that are described only within the registry.

This function can be used to store EWF-specific state information and can be useful when upgrading a device. Persistent data is stored in the EWF volume store.


OS Versions: Windows XP Embedded.
Header: Ewfapi.h.
Link Library: Ewfapi.dll, Ewfapi.lib.

Code Example

The following routine(s), which are included in the EWF API Code Sample (Sample.cpp), demonstrate how to use this function:


See Also

EWF API Functions | EwfMgrGetPersistentData | EWF API Code Sample

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