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How to Reset the Cisco DPC3939 XFINITY

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Setup Router Staff
(Last Updated: ) | Reading Time: 3 minutes

On this page we will be showing you how to reset the Cisco DPC3939 XFINITY router back to factory default settings. It's important before we begin that you know the difference between a reboot and a reset. A reboot is a cycle of the power to the device. The device turns off, then restarts. On the other hand a reset is taking all the settings and returning them all back to factory defaults.

Warning: Be careful when resetting this router. There are consequences to this action. Please consider the following before continuing:

  • The router's setup username and password are reverted to factory settings.
  • The Internet security and password are reverted to default.
  • If you are resetting a DSL router you need to re-enter the ISP username and password to continue using the Internet. Call your Internet Service Provider for more details.
  • If you have changed any other settings such as an IP address or port forward they need to be reconfigured after the reset is complete.

Other Cisco DPC3939 XFINITY Guides

This is the reset router guide for the Cisco DPC3939 XFINITY. We also have the following guides for the same router:

Reset the Cisco DPC3939 XFINITY

Use a VPN Instead

Have you considered using a VPN instead of forwarding a port? For most users, a VPN is a much simpler and more secure choice than forwarding a port.

We use and recommend NordVPN because not only is it the fastest VPN, it includes a new feature called Meshnet that makes forwarding a port no longer necessary for most applications. With NordVPN Meshnet, you can connect to your devices from anywhere in the world, completely secure, over a highly encrypted VPN tunnel.

When shopping for a VPN, make sure that they meet the following criteria:

  • Your VPN provider should have a no-logs policy. This means that they do not keep any logs of any kind.
  • Make sure that your VPN provider has lots of exit nodes all around the world.
  • Check that your VPN will not affect your speed.
  • Verify that your VPN provider uses WireGuard as the underlying protocol.
  • Many people prefer a VPN provider that is not based in the United States.

This is the list of requirements that we used when we were shopping around for a VPN provider. There are lots of free, shady VPN providers out there that we looked at and dismissed.

Based in Panama, using diskless servers, and with over 6,100 servers in 61 countries, we can safely say that NordVPN satisfies all of these requirements.

NordVPN is the fastest VPN!

Once you've set up your NordVPN account on multiple computers and enabled Meshnet, you can seamlessly access all of your devices as if they were on the same network. You don't even have to log in to your router. It's very simple.

Every time you click on one of our affiliate links, such as NordVPN, we get a little kickback for introducing you to the service. Think of us as your VPN wingman.

The first step in resetting any device is to know where the reset button is located. This small recessed button is on the back side of the router. Take a look at the image below for reference.

router reset factory settings
This is the reset page from your Cisco DPC3939 XFINITY router.

Take a pin or unwound paperclip and press down on the reset button for more than 10 seconds. This is important because if you only hold it down for a couple seconds you will simply reboot the router instead of resetting it like you wanted.

Please be sure you understand that this reset is going to erase everything you have changed in your router. To avoid having to reconfigure the entire router you should try other options first.

Login to the Cisco DPC3939 XFINITY

Now that you have finished resetting the router you need to login to the Cisco DPC3939 XFINITY router to reconfigure it. To do this you need to know what the default IP address, username, and password are. We have gathered these for you and included them in our Cisco DPC3939 XFINITY Login Guide.

Change Your Password

Now you should change the default password. If you need help, check out our Choosing a Strong Password guide.

Tip: If you keep this router in your home it's okay to write this new password down on a piece of paper and attach it to the bottom of the router for future reference.

Setup WiFi on the Cisco DPC3939 XFINITY

Now take a look at your wireless security settings. The encryption or security method should be set to WPA2 along with a strong password. If you think you need help with this part, check out our guide titled How to Setup WiFi on the Cisco DPC3939 XFINITY.

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Cisco DPC3939 XFINITY Help

Be sure to check out our other Cisco DPC3939 XFINITY info that you might be interested in.

This is the reset router guide for the Cisco DPC3939 XFINITY. We also have the following guides for the same router: