dn := uint32(50)
	for {
		b := make([]byte, n)
		db := make([]uint16, dn)
		sid = (*SID)(unsafe.Pointer(&b[0]))
		e = LookupAccountName(sys, acc, sid, &n, &db[0], &dn, &accType)
		if e == nil {
			return sid, UTF16ToString(db), accType, nil
		}
		if e != ERROR_INSUFFICIENT_BUFFER {
			return nil, "", 0, e
		}
		if n <= uint32(len(b)) {
			return nil, "", 0, e
		}
	}
}