Fix Destination Host Unreachable Ping Error Reply

During my network engineer career, one of the common ICMP errors I received while troubleshooting connectivity issues was Destination Host Unreachable.

This error was the cause of my Internet connectivity problems most times.

The same can be true for you too.

Once you learn to resolve this error, you can fix most of your Internet connectivity problems. In this tutorial, I will explain everything about this error.

1. The first part of this tutorial explains the meaning of the ICMP reply Destination Host Unreachable.

   
   

2. The second part explains the reasons for the ping reply Destination Host Unreachable.

   
   

3. The third part explains the steps to fix this error message.

So, let us check the meaning of the ping reply Destination Host Unreachable.

Before proceeding to the core of this tutorial, let me explain the meaning of this ping reply.

Now you understand the meaning of this ping reply. However, you should ask yourself two questions to learn more.

1. Who replied to your device with this Destination Host Unreachable message?

   
   
   

2. Why the ping packets from your computer failed to reach the destination address?

Let me answer the questions one by one. But before I explain the first question, you must learn how the ping operation works.

I am pinging my blog by typing ping www.corenetworkz.com on the Command Prompt.

The complete process is below.

• ICMP Echo Requests travel out of my computer through the network adapter.

  
  

• Ping packets reach the default gateway. The default gateway is the router in most cases.

  
  

• The default gateway needs to find a route to the destination address. So, the next step is checking the ARP table and Routing table.

  
  

• Default Gateway finds a route to the Remote Gateway of the destination IP address.

  
  

• Remote Gateway receives the packets.

  
  

• Remote Gateway forwards the ping packets to the remote host (the final destination - server of CoreNetworkZ.com).

  
  

• The Remote Host (web server of CoreNetworkZ.com) acknowledges by sending ICMP Echo Replies.

  
  

Can you tell me the potential sources for a Destination Host Unreachable reply from this ping workflow algorithm?

You can get this reply from two possible sources.

1. Your Default Gateway

   
   

2. Remote Gateway

How do we know whether the reply comes from the Default Gateway or Remote Gateway?

Well, it is simple.

All you have to do is to analyze the ping reply carefully.

Check the format of the message. It comes in two different forms.

1. Reply from x.x.x.x Destination Host Unreachable

   If you see the following format, check the IP address.

   
   

   Most of the time, x.x.x.x must be a Remote Gateway address.

   
   

   Which shows the error message you received is from the Remote Gateway.

   
   
   

2. Destination Host Unreachable

   If you don't see an IP address in the error replies, they came from the Default Gateway.

   
   

   In a home network, your home router is the Default Gateway.

   
   

Both error formats have different reasons. I will explain the reasons in the next part.

Let us check why your computer displays the message Reply From x.x.x.x Destination Host Unreachable.

Have a look at the list below.

One of the reasons listed below can get you to the ICMP Echo message Destination Host Unreachable.

1. Your Default Gateway doesn't know the route to the destination IP address.

   
   

2. Packet Routing issues on Remote Gateway.

   
   

3. The destination host might be down.

   
   

4. Loose Connection.

   
   

5. Strict Firewall Settings.

   
   

One of the frequent questions I receive from our readers is whether this error is related to Operating Systems ( like Windows and Linux ).

The answer is no.

Analyzing the ICMP Echo Destination Host Unreachable

Let me explain why I received this ICMP Echo Reply by analyzing a live example.

I send ping packets to the global DNS address 4.2.2.2 to troubleshoot the connectivity problem. The screenshot below shows the reply I received.

Microsoft Windows [Version 6.1.7600]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\corenetworkz;ping 4.2.2.2

Pinging 4.2.2.2 with 32 bytes of data:

Destination host unreachable.
Destination host unreachable.
Destination host unreachable.
Destination host unreachable.

Ping statistics for 4.2.2.2:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

C:\corenetworkz>

Which format is this?

It is the second format of the Destination Host Unreachable error.

The final part of this tutorial explains the procedure to fix the ICMP Error Reply Destination Host Unreachable.

To understand more, I recommend you check the discussions by visiting the link below.

If you do not want to go into the complexity of this ICMP Echo Reply, you can follow the instructions below to resolve the Destination Host Unreachable Ping error message.

1. Turn Off The Firewall

   Aggressive firewall settings can interrupt the ICMP Echo Requests and cause the Destination Host Unreachable error.

   
   

   Turn Off the Firewall to check whether the firewall is the reason for this issue on your computer.

   
   

   Try to access the Internet after the firewall is Off.

   Also, Ping a Web URL and check whether the issue persists. If so, go to the second solution.

   
   
   

2. Power Cycle The Network

   A loose connection in your home network can invite the Destination Host Unreachable ICMP Echo Reply.

   
   

   Outdated Routing and ARP tables also result in Ping errors.

   
   

   A proper home network Power Cycle can fix this. Let us check the steps.

   
   

   • Switch off every device in the network.

     
     

   • Disconnect power cables from Modem, PC, and Router.

     
     

   • Disconnect the Ethernet cables from Modem, Computer, and Router.

     
     

   • Reconnect the power and ethernet cables.

     
     

   • Power On the Modem and wait for one minute.

     
     

   • Power On the Router and wait for one minute.

     
     

   • Power On the PC and ping Google to check whether the Destination Host Unreachable error persists.

   
   

   A proper Power Cycle will fix issues like corrupted ARP and Routing tables and loose connections.

   
   

   If the issue persists, go to the final solution.

   
   
   

3. Disable IPv6 and Test the Connectivity

   Sometimes devices fall into IP version conflicts. Different operating systems have separate IP version priorities.

   
   

   Windows 10 prefers IPv6 to IPv4. Linux variants like Ubuntu, Fedora, and Debian prefer IPv6 to IPv4.

   
   

   However, sometimes devices fail to work with IPv6.

   Rarely it results in ICMP error messages. We can check it by turning off the IPv6 on your device.

   Let us check how to turn off the IP Version 6 on a Windows 11 computer and test whether it fixes the Destination Host Unreachable issue.

   
   
   
   • Right-click on the Network Adapter at the system tray.
     
     
   • Click on Open Network & Internet settings.
     
     
   • Click on Change Adapter options.
     
     
   • Right Click on the current connection and click properties.
     
     
   • Uncheck the Internet Protocol Version 6 (TCP/IPv6).
     
     
   • Click OK
     
     
   • Reboot your Computer.
     
     
   Once you reboot your computer, check for the connection.

You have learned to troubleshoot the Destination Host Unreachable Ping error message on Windows and Linux Systems and fix it.

We suggest you read similar tutorials to learn more about Computer Network Troubleshooting.