Title Page

About This Document

Contents

Fault Diagnosis Method

System Maintenance

Common Configuration Problems Causing Faults

Troubleshooting for Password

Troubleshooting for Hardware

Startup Faults

Troubleshooting for License

Troubleshooting for System Management Faults

Troubleshooting for Network Connection

Troubleshooting a 3G Access Failure Using the Diagnosis Center

Troubleshooting an XDSL Access Failure Using the Diagnosis Center

Troubleshooting for WLAN Faults

Troubleshooting for L2TP Faults

Troubleshooting for IPSec Faults

Troubleshooting for SSL VPN Faults

Troubleshooting for Physical Interface Faults

Troubleshooting for Route Faults

Troubleshooting for IP Address Faults

Troubleshooting for ARP Faults

Troubleshooting for DNS Faults

Troubleshooting for IPv6 Faults

Troubleshooting for Multicast

Troubleshooting for NAT Faults

Troubleshooting for Internet Access User Authentication Faults

Troubleshooting for QoS Faults

Troubleshooting for Reliability

Troubleshooting for UTM Faults (USG2200 5100 5500 USG2200 5100 HSR)

Troubleshooting for UTM Faults (USG2110-X 2100 USG2100HSR)

How to Obtain Technical Support