somSelf (M_WPAbstract *) - input
pszSetting (PSZ) - input
pValue (PVOID) - in/out
If this parameter is NULL, only the length of the value of the setting is returned.
ulValueLen (ULONG) - input
ulReturnedData (ULONG) - returns
A return value of 0 indicates an error occurred, in which case no data is returned in pValue.