ASUS DSL-AC88U Modem Router - AC3100, Dual-Band, Gigabit Ethernet, VDSL2

Log into the ASUSWRT interface, navigate to the Administration section, and click on the Firmware Upgrade tab. Follow the on-screen instructions.

You will need to reset the router to factory settings. Press and hold the reset button on the back of the router for about 5-10 seconds until the power LED starts blinking. Then, reconfigure the router.

Yes, you can connect external storage devices to the USB ports and share files with devices on your network. You can also connect a printer.

Log into the ASUSWRT interface, go to the Wireless settings, and change the SSID and password for each band (2.4 GHz and 5 GHz) as desired.

Yes, the ASUS DSL-AC88U supports VPN server (PPTP/Open VPN) and VPN client (PPTP/L2TP/Open VPN) configurations.

Place the router in a central location, away from obstructions. Utilize the 5 GHz band for faster speeds over shorter distances. Consider using a Wi-Fi range extender.

The warranty period is typically two years from the date of purchase. Please check the included documentation for detailed warranty information.

Check the physical connections (DSL cable or Ethernet cable). Reboot the modem and the router. Verify the internet service is active by contacting your ISP. Ensure the correct username and password are used if required by your ISP.

Move the router to a more central location. Reduce interference from other electronic devices. Change the Wi-Fi channel in the ASUSWRT interface to a less congested one. Ensure your devices are close enough to the router.

Check the router's placement for obstructions. Update the router's firmware. Reduce the number of devices connected to the network. Configure QoS (Quality of Service) settings to prioritize certain traffic.

Ensure your device is connected to the router's network. Check the router's IP address (192.168.1.1 or as configured). Try resetting the router to its factory defaults.