Reset the Sagemcom Fast 3864AC

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

This guide shows you how to reset your Sagemcom Fast 3864AC router to factory default settings. Resetting a router is different than rebooting a router. Every time your router loses power it reboots. This is very different from a reset, which erases a router completely and returns it to factory default settings.

Warning: Before you continue, there are a few things you need to know. The following settings will be changed in your router:

  • The router's login and password are reset.
  • All WiFi settings are reset, including network name and password.
  • Your ISP username and password will be reset, and you may have to contact your ISP.
  • All port forwards, firewall settings, and parental controls that you have configured will be removed.

A router reset is the last step you should take in recovering your router's password. You should be sure that you have tried to at least recover your router password using our Router Password Finder before resorting to a router reset.

Other Sagemcom Fast 3864AC Guides

This is the reset router guide for the Sagemcom Fast 3864AC 8.379 Optus. We also have the following guides for the same router:

Recover Password in Sagemcom Fast 3864AC

Before you resort to doing a full router reset, you may want to try running our Router Password Finder first.

Our Router Password Finder can recover your lost or forgotten router password without doing a full router reset, which can save you lots of time.

Router Password Finder - Lost or Forgotten Router Password Recovery Tool

Do not do a full router reset until after you have tried every other option to log in to your router.

Reset the Sagemcom Fast 3864AC

Most routers have a small button on either the back or the bottom. Most reset buttons look like this:

Router Reset Button

Reset buttons are usually tiny. Yours may look slightly different than this. Sometimes the button is under a pinhole, and you need a paper clip to push it.

Keep an eye on the lights on the front of your router while holding the reset button down for about 10 seconds. The blinking pattern of the lights on the front of the router should change when the reset is complete. Do not be concerned about holding the reset button down too long. It will not hurt anything.

Don't forget, this step will totally reset your Sagemcom Fast 3864AC router back to factory settings.

Only do this once you have exhausted all other troubleshooting options, such as running our Router Password Finder software, which can recover a lost router password for you.

Login to the Sagemcom Fast 3864AC

Now you need to log in using the factory default username and password. We have a Fast 3864AC Login Guide with all this information ready for you.

Change Your Password

After logging in to your router for the first time, you need to change your router's password. Since factory passwords are well known, it's a huge security risk to leave your router set to the default. Our Choosing a Strong Password guide talks about choosing a strong password for your router.

Tip: After creating this new password, we highly recommend writing this down on a post-it note and attaching it to the bottom of your router for future reference.

Other Sagemcom Fast 3864AC Guides

We have collected a lot of information about the Sagemcom Fast 3864AC router. You can find some of our additional content here.

This is the reset router guide for the Sagemcom Fast 3864AC 8.379 Optus. We also have the following guides for the same router: