Best 5 Fixes for DHCP Error 0x79
Quick Solutions to Resolve DHCP Error 0x79 and Get Your Network Up & Running Again

DHCP error 0x79 is an issue that can cause several effects, ranging from preventing users from connecting to the network to blocking access to the internet to slowing down network operations.
However, there are a variety of solutions that can help to address the issue. In this article, we will explore the best fixes for DHCP Error 0x79 and provide tips on how to get your network back up and running quickly.
What is the DHCP Error 0x79, and what causes it?
The DHCP error 0x79 is a No Subnet Mask error. By this, we mean that the DHCP server cannot determine the subnet mask associated with the IP address it attempts to assign to the client. This network-related error occurs when the DHCP server cannot obtain an IP address for a client.
The error can occur for several reasons, and some of those reasons may include:
- Incomplete DNS records: The DHCP Error 0x79 occurs when the Domain Name System (DNS) records are incomplete or incorrect.
- Incorrect IP address: The error may also occur if the IP address assigned to the network device is incorrect or invalid. This could be due to faulty subnet masks or settings in the DHCP server.
- Corrupted DHCP database: The error may also occur if the DHCP server database is corrupt. It can also be because of an issue with the DHCP server software.
- DHCP server disabled: The error can also occur if the DHCP server is not enabled.
- Invalid lease time: The error can also occur if the DHCP server has a configuration with an invalid lease time.
- Network issues: Finally, the error may result from network issues such as packet loss, network congestion, or other network-related problems.
How do I fix DHCP Error 0x79?
Before you start applying the solutions below, do the following checks:
- Check your connection: Do checks like checking the network cables, checking any network settings that may be incorrect, restarting the router/modem, and possibly resetting the router/modem.
- DHCP Range: Check the DHCP range on your router.
- Automatic obtaining of IP address: Verify that your computer is configured to obtain an address automatically.
1. Run chkdsk command
- Press Windows + S keys together to start Search Box.
- Enter Windows PowerShell in the search field, then click on the app to open it.
- Enter the command below and press Enter:
chkdsk d: /f
(where d: is your volume drive)
2. Check the hard drive status
- Press Windows + S together to open Search Box.
- Enter Security and Maintenance in the search area, then click it.
- Then, click on the drop-down menu of Maintenance and review the status.
- If you discover something wrong, you can try the solution 1 above.
3. Disable the Internet Protocol Version 6 (IPv6)
- Right-click on the Network icon in the system tray of your PC, then click on Network and Sharing Center.
- After that, click on Change Adapter Settings.
- Then, right-click on your network adapter and select properties.
- Then, click the Internet Protocol Version 6 box to uncheck it.
- Finally, click OK.
4. Use Command Prompt
- Press Windows + S together to open Search Box.
- Enter cmd in the search area, then click Run as administrator to use administrator privileges.
- When the Command Prompt console opens, enter the following commands one after the other and click Enter after each entry:
netsh winsock reset catalog
netsh int ipv4 reset reset.log
netsh int ipv6 reset reset.log
- Finally, restart your PC.
5. Reconfigure the LAN cable and wireless connection
- Right-click on your Ethernet adapter properties.
- Then, click on Internet Protocol Version 4 (TCP/IPv4) and click on the Properties button.
- Then, select Use the following IP address: option and set the IPs below:
IP address: 192.1xx.1.10
Subnet mask: 255.255.255.0
Default gateway: use your router IP address, e.g. 192.1xx.1.1 - After that, choose Use the following DNS server addresses: form the second section and set PreferAlternate DNS server: with your router default IP, e.g., 192.168.1.1
- Finally, click on OK and try connecting through the LAN and then the wireless connection.
To conclude, the DHCP Error 0x79 is a common issue that can cause many problems with your network. However, you can fix them to get your network back up and running quickly.
Following the five fixes outlined above, you can skillfully troubleshoot and resolve the DHCP Error 0x79. Once you’ve fixed the issue, you can enjoy a more reliable and secure network.