Fixing guide to VPN Error 721 – The remote computer is not responding

You may receive the following error message when you try to connect with a VPN using the Point-to-Point Tunnelling Protocol (PPTP) client.

Error 721: The remote computer is not responding.

In this article, I will tell you some useful methods to fix VPN error 721 on Windows 8, 8.1, 10, 11, or Windows server machines.

Why VPN Error 721?

Today, Virtual Private Network (VPN) is very popular among computer users. The days have gone when only companies used this service. Today a normal computer user runs VPN on their machine. You can receive the VPN error code 721, due to one of the following reasons:

  1. Network firewall is blocking the connection.
  2. Antivirus is stopping the service.
  3. Misconfigured VPN Settings.
  4. VPN server is down
  5. Windows is malfunctioning, etc.
How to Fix VPN Error 721?

In order to fix VPN Error 721, follow the methods given below.

Method 1: Fix using the Advanced System Repair Tool

Most of the time, this error appears due to corrupted system files, missing system files, outdated software and drives, problems in registry files, etc. It is better to optimize your PC and fix the hidden bugs to resolve this VPN problem. The Advanced system repair tool is one of the best PC repair tools that scan and fix your PC problems and enhance PC speed by 2 times.

3 Steps to Fix this Error
Step 1. Download Advanced System Repair Pro [File Size: 16.4 MB]
Step 2. SCAN your Windows PC
Step 3. Click Fix button to Repair Error

Method 2: Network firewall does not permit Generic Routing Encapsulation (GRE) Protocol.

This is one of the main reasons behind VPN Error Code 721. PPTP (Point-to-Point Tunnelling Protocol) uses GRE (Generic Routing Encapsulation) to tunnel data. Sometimes the network firewall does not permit GRE to tunnel data over port 47. Port 47 is the default port for the GRE protocol.

To resolve this issue, you need to set up the following things.

1. Configure the network firewall so it could allow GRE protocol 47.
2. Also make sure that the network firewall permits TCP traffic on port 1723.
Configure Network Firewall to allow GRE protocol 47 and permits TCP traffic on Port 1723.
Step 1: Log in to your Firewall.
Step 1: Go to the Firewall > Service. At the bottom click on Add button.
Step 1: Give the name GRE. Select GRE (47) protocol and click Ok.
Step 1: Save and close the Firewall.

Method 3: Restart Router

Restart is a great remedy for any type of electronic device. Just restart the router and then try to connect VPN.

Summary

In this article, I explained what VPN Error 721 is and Why it appears. I also explained how you can fix this error on your machine.