---
title: "WIZ750SR DHCP hostname invalid"
url: "https://maker.wiznet.io/forum/14683"
markdown_url: "https://maker.wiznet.io/forum/14683/md"
type: "Forum topic"
category: "Serial-to-Ethernet & ConfigTool"
author: "bobby.henderson"
created: "2022-10-17T14:38:51+09:00"
last_activity: "2025-05-27T01:48:17+09:00"
language: "en"
views: 336
replies: 2
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# WIZ750SR DHCP hostname invalid

## Question

Asked by bobby.henderson on 2022-10-17 in Serial-to-Ethernet & ConfigTool.

The client address used in the DHCP discovery message includes an illegal escape character: WIZnetsc\026.mydomain.net

This is caused by a software error at:
WIZ750SR/ioLibrary/Internet/DHCP/dhcp.c:509

When will a fix be released?

## Replies

### Reply 1 by irina, 2022-10-24

Hi~
Please let me know under what circumstances the issue arises.
An error capture picture file is also good.

### Reply 2 by lcnittl, 2025-05-27 (in reply to reply 1)

We are also encountering an issue where the DHCP discovery messages contain improperly formatted characters. Specifically, the MAC address appended to the hostname appears to be inserted as raw bytes rather than as an ASCII-encoded hexadecimal string. This results in non-printable or invalid characters in the hostname field, which can cause issues with DHCP servers and network monitoring tools.

We are aware of an open pull request on your GitHub repository ([WIZ750SR#30](https://github.com/Wiznet/WIZ750SR/pull/30)) that addresses this problem by properly encoding the MAC address as ASCII. However, this patch has unfortunatley not yet been merged into the official firmware.

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Source: https://maker.wiznet.io/forum/14683