[DllImport("Crypt32.dll", SetLastError = true)]
public static extern bool CryptUnprotectData(
ref DATA_BLOB pDataIn,
StringBuilder ppszDataDescr,
ref DATA_BLOB pOptionalEntropy,
IntPtr pvReserved,
ref CRYPTPROTECT_PROMPTSTRUCT pPromptStruct,
uint dwFlags,
ref DATA_BLOB pDataOut
);