This document provides troubleshooting tips to why mobile user cannot connect to the server.
1. a UTT Business Router (hereinafter shorted as “the Router"), such as UTT router N518W, AC750W, AC750GW, AC1220GW, ER518, ER840G and ER4240G. Firmware Version: 3.0.0 or above
2. a PC/laptop connected to the Router wirelessly or through an Ethernet cable
1. Check VPN status at VPN > PPTP/L2TP, tunnel test2 shows offline.
2. If it reports error as the below, please check the user name and password of the VPN tunnel. (It is recommended that delete original VPN and reestablish.) If not, please skip to step 3.
3. If it reports error as the below, please check the Internet on both server and client.
4. Ping WAN IP of the server side from mobile user client to check the public IP address is available.
5. Check VPN Status and Connection Sessions at VPN > PPTP/L2TP > PPTP Global Settings, one means there is only one VPN tunnel can be connected at the same time.
6. Extend Max Connections and save the change.
7. Test re-dial the VPN server and successfully connect.