[Solved] Error 651 – Connection Failed with Error 651 in Windows

You might have faced error 651 on your computer if you are a Windows user. It is a common problem faced by many Windows users (Especially for Windows 11 users). So before we get into the topic, first let’s see why this error occurs.

Why does error 651 occur?

Error 651 is a common Windows error which usually occurs when we try to establish an internet connection using PPPoE connections. This error occurs due to various reasons such as:

  • Raspppoe.sys file has been saved in the wrong location.
  • Registry errors.
  • IP address conflict.

If this error occurs, then you might see this message Error 651: The modem (or the other connecting device) has reported an error and usually the message will be titled “Connection failed with error 651”.

So how to solve this error? well, there is no official solution to fix this error, but there are some common troubleshooting methods which work for many users. I have collected some of the best working solutions that will help you to solve this error.

Understanding “Connection Failed with Error 651”

The primary culprit behind the “Connection Failed with Error 651” is often linked to issues with the modem connection. This error is particularly prevalent in Windows 7 and 8, especially when utilizing a PPPoE modem connection.

When attempting to browse a webpage or run applications that require network connectivity, the error 651 may appear on your screen. This error surfaces when trying to connect to your modem from the available networks in the system tray. 

The accompanying message reads, “Error 651: The modem (or another connection device) has reported an error.” 

Error 651 is a message indicating that the connection couldn’t be completed, either due to the modem being inaccessible or encountering an authentication problem. Unfortunately, there’s no official method specified for resolving this error. However, below are some troubleshooting steps th

How to Fix Connection Failed with Error 651 in Windows

I have compiled a list of solutions that I have collected from various forums and help centers, all these solutions worked for many people and I’m sure that one of below solution will definitely work for you. So let’s start from basic troubleshooting steps to advance one.

1. Use a Different Connection

Consider experimenting with an alternative connection before delving into troubleshooting methods related to the system. Give a different connection a shot to assess whether the problem lies within the system itself or is associated with the connected device. This simple step can aid in pinpointing the source of the issue more effectively.

2. Reconnect Your Router or Other Connecting Device

Fix slow WiFi - Restart the Router

This is the most basic troubleshooting step, One can simply solve this error by reconnecting the internet connecting device. So if you are using router then simply turn off your router and after 5 minutes turn it on or if you are using LAN connection then unplug the wire and plug it back.

3. Reset TCP/IP On Your PC

Resetting the Windows networking stack can solve error 651 and luckily Windows 8/10 comes with a built-in tool you can use to do this just follow the below steps.

  • Launch command prompt with administrative right.
  • Copy the command given below and hit enter

netsh int ip reset reset.log 

  • Restart your computer and hopefully, the problem will be solved.

4. Initiate the Network Troubleshooter

If you encounter network errors on your Windows PC, kick off the troubleshooting process by running the built-in Network troubleshooter. It’s a practical starting point that can identify and resolve a variety of connection issues you may encounter with your PC.

Follow these steps:

  • Type “Control Panel” in the taskbar search area and click Open.
  • In the ensuing window, enter “Troubleshoot” in the top-right search bar and choose “Troubleshooting” in Control Panel.
  • Select “View all” from the left pane.
  • You’ll now see a list of available troubleshooters in Windows. Look for “Internet Connections” and right-click on it.
  • Choose “Run” from the context menu and follow the on-screen instructions.
  • Allow the troubleshooter to complete its scan. If it proposes fixes, click “Apply this fix.” If not, click “Close the troubleshooter.”
  • Repeat the same steps for “Incoming Connections” and “Network Adapter.”
  • Afterward, restart your PC and check if the issue persists.

This method uses the Control Panel, but if you prefer a simpler approach, you can run the troubleshooter through Windows Settings:

  • Press Win + I to open Windows Settings.
  • Choose “Troubleshoot” from the left pane.
  • Locate the “Internet Connections” troubleshooter in the right pane.
  • If you can’t find it, click on “Other troubleshooters” in the right pane.
  • Find the “Internet Connections” troubleshooter and click “Run.”
  • If the initial scan identifies problems, click “Apply this fix.”
  • If no issues are found, select “Close the troubleshooter” and proceed to the next method below.

5. Recreating Dial-Up Connection

Your internet connecting device might get hanged during the connection. So recreating your dial-up connection can fix this issue. So simply right click your Dial-Up or Broadband connection and select create copy and then delete your existing connection. Confused? Just follow the step by steps guide given below.

  • Open Network & Sharing Center and click on Change Adapter Setting.
  • Now right click your broadband or dial-up connection and select Create Copy.

Fix error 651 - solution 4

  • This will create a copy of your existing connection.
  • Now simply delete your old connection and redial the new connection.

6. Disable Auto Tuning Feature

Windows Auto tuning feature is used to improve the performance of programs which receive TCP data from a network. If you are using a router then this method can do the magic, Follow the below steps to disable the auto-tuning feature.

  • Launch command prompt with administrative rights.
  • Copy the below command and paste it in command prompt

Netsh interface tcp set global autotuning=disabled

  • Now just try to restart/reconnect your internet connection.

7. Disable IPv6 of your Internet Connection

This solution worked for many users. You can simply disable IPv6 to fix this error. Follow the below guide to disable IPv6.

  • Open Control Panel and select Network & Internet.
  • Further, choose the Network & Sharing Center option.
  • Now click on your active network connection.

Fix error 651 - solution 5

  • Select Properties and switch to Networking tab.

  • Untick/Uncheck Internet Protocol version 6 (TCP/IPv6) and click on Ok.

8. Reinstall Network Adapter

This is the most working troubleshooting step when it comes to an internet connection problem. You can simply reinstall the network adapter to fix Connection Failed with Error 651 problem. Just follow the below guide to reinstall the network adapter.

  • Go to Start and search for devmgmt.msc.
  • Double click it to launch device manager, Now look for Network Adapters Category and click the “+” icon it’s left.

  • Now right-click the first network adapter and select uninstall.
  • Restart your computer and your network adapter will get automatically reinstalled.

9. Re-register “raspppoe.sys” File

You may face error 651 due to “raspppoe.sys” file fails to load while connecting to the internet. So to fix this you can try re-registering the raspppoe.sys file.

  • Open the command prompt with administrative rights.
  • Now type the following command and press enter.
    regsvr32 raspppoe.sys
  • This command will re-register the raspppoe.sys file which indirectly causes error 651.

10. Keep Network Drivers Up-to-Date

Maintaining up-to-date and efficient network drivers is crucial for a smooth and trouble-free connection. If you’re facing connectivity issues, especially due to outdated drivers, updating them can often resolve the problem. Follow these straightforward steps:

  • Enter “Device Manager” in the Windows Search bar and open it.
  • In the Device Manager window, locate and expand the “Network adapters” section.
  • Identify your wireless adapter, and right-click on it.
  • From the context menu, select “Update driver.”
  • In the ensuing window, opt for “Search automatically for drivers.” The system will install any available updated driver it finds.
  • Once the process is complete, close the Device Manager window and verify if the issue is resolved.
  • Ensuring your network drivers are current is a practical step in troubleshooting connectivity problems.

11. Perform Clean Boot

If there is a problem in Windows services then performing a clean boot can fix your problem, to perform a clean boot we simply need to disable all other services. Simply follow the below guide to perform a clean boot on your computer.

  • Go to the Start menu and search for msconfig.exe
  • Click it to launch Windows configuration.
  • Now under the general tab click on Selective Startup and select Load startup items

  • Now switch to Services tab and check Hide all Microsoft services.
  • After that just click on Disable all to disable all other services.

Fix error 651 - solution 7

  • Now simply just restart your pc to perform a clean boot.

12- Restore Windows Network Configuration to Default

The final method in our troubleshooting repertoire involves resetting Windows’ network configuration to its default state.

Should the issue be rooted in a glitch within the network configuration, this reset can often circumvent the error. However, it’s essential to note that this method may result in the loss of saved connections.

How to Resolve Error 651 in Windows 7 and 8

It’s worth noting that Error 651 in LAN connections isn’t exclusive to Windows 10; users of Windows 7 and 8 may also encounter this issue. The error often arises from communication challenges between the PC’s network hardware and the router or modem. If you’re using Windows 7 or 8 and find yourself facing Error 651, you can explore the solutions outlined above for Windows 10. These four methods are commonly effective for resolving Error 651 in Windows 8 and 7:

  • Restart the Network Device and/or Computer: A simple yet effective initial step is to restart either your network device or the entire computer. This can often resolve temporary glitches causing connectivity issues.
  • Update and/or Reinstall the Network Adapter’s Driver Software: Ensure your network adapter’s driver is up-to-date. If not, consider updating it. Alternatively, reinstalling the driver can address any corrupted files that might be contributing to the problem.
  • Replace the Current Version of the File “raspppoe.sys”: In cases where the “raspppoe.sys” file is implicated, replacing the existing version may resolve the issue. Ensure you have a reliable and updated copy of this file for the replacement.
  • Manually Define the Maximum Broadband Speed: Manually setting the maximum broadband speed is another strategy. This involves specifying the speed parameters and can sometimes optimize the connection, particularly if automatic settings are causing conflicts.

Applying these methods can often help alleviate the Error 651 issue on Windows 7 and 8 systems.

Frequently Asked Questions for Error 651?

What is Error 651 On Internet Connection?

Error 651 on Internet Connection indicates that there is some issue with your modem device. This error usually occurs on Windows devices. The reason for error 651 could be incorrect IP configuration or a network card driver issue

What is WAN Miniport PPPoE Error 651?

PPPoE stands for point-to-point protocol over Ethernet. This error occurs when a user tries to connect Windows 7 with an internet connection. It occurs because of a weak network connection.

How Do I Fix PPPoE Connection?

To fix the PPPoE Connection, you need to pay a visit to control panel settings of your Windows PC. Under the settings “Network and Sharing Center”, select broadband (PPPoE) and fix it.

What To Do When The DNS Server Isn’t Responding?

When the DNS server isn’t responding, you should first try restarting your computer. If it doesn’t help, check your router configuration and settings. Eventually, you may reset the router to the default settings.

I hope the above solutions helped you in solving error 651, If not then it might be your ISP’s issue, you should immediately contact your internet service provider (ISP) and report this issue.


  1. Thank you, thank you, thank you! After a Windows 10 install, I ignored your instruction about restarting the router because my tablet was connected. Weeks later, out of sheer frustration, I restarted the router. Worked beautifully! Sorry for ever doubting you.

  2. Found the simple solution! Just click open the Bluetooth switch! Recent windows 10 update caused my laptop unable to connect to the wifi.

  3. Just helped a friend fix this on his W10 laptop. He had an unused dial-up phone modem on his laptop. Uninstalled it and rebooted and started working.

  4. Thanks very much – no.2 (which was proposed by other websites too) did the trick for us. We were re-establishing wifi after dad received new router and Windows 10 didn’t adjust to it.

  5. #2 Worked for me – thank you so much! Lost internet connectivity after hard power outage. Tried multiple things then found this site. Keep up the fine work!

  6. New MB/Processor with same HDD’s from previous MB, and internet is physically in the CAT-5 port, yet system says not connected. 651 error on all attempts. Suggestions?

  7. Great Article. Uninstalling the Network Adapter and restarting the PC worked liked a charm for my DLINK DSL-2730U Modem Router. This was my first installation sequence, thanks a lot Abhishek.


Please enter your comment!
Please enter your name here