If your eero network’s SSID is the same as your old network and your Windows device isn’t connecting, you will need to manually "Forget the network" on your Windows device in order to supply new credentials and reconnect.
The way you forget a network depends on the version of Windows you’re running:
Windows 7
- Start Network and Sharing Center
- In the Tasks pane, click Manage wireless networks
- Right-click the connection you want to delete, and then click Remove network
- In the Manage Wireless Networks - Warning dialog box, click OK
Windows 8
- Open the charm bar.
- Mouse: Move your mouse to the very top-right of the screen
- Touchscreen: Swiping in from the right-hand side of the screen
- Keyboard: Hold down the "Windows Key" + C at the same time
- Select "Settings"
- Select "Available" or "Network"
- Right click on the network you want to remove. Select "Forget this network"
Windows 10
- Press Win+I to open the Settings app
- Select Network & Internet
- Next click on Wi-Fi in the left panel
- There you will see a link Manage Wi-Fi Settings. Click on it
- In the window which opens, you will see two settings – Wi-Fi Sense and Manage known networks
- Under Manage known networks, select the network, and you will see two options – Share and Forget
- Click on Forget. This will delete the Wireless Network’s profile and connection details