1, there is something wrong with the routing and connection: many times the vpn problem is simple, but there is something wrong with the routing and connection. At this time, it is very easy to solve by simply changing the routing and connection mode of vpn. For example, our common pptp6 19 error is this problem. At this point, we only need to change the connection mode and use it with other VPN connection modes (such as L2TP or OpenVPN). If you just suspect that it is a routing problem, you can use the ping command to test whether it works. If it doesn't work, it's a route problem and can be changed.
2. Error code problem: In our windows system, wpn connection is set manually, and sometimes there is an error code problem. If there are problems such as 768/6 19/868, you can refer to the error code encyclopedia to solve them. If you don't use windows system, the mac or ios system will prompt that the authentication failed, that is, the account expired or the password was incorrectly filled. We can solve it by checking in turn.
3. System or network restrictions: This problem generally appears in the public environment of Internet cafes or companies, because it is easy to restrict vpn connections in public environment. If the system is restricted, it means that vpn connection cannot be created, and the whole dress is gray. Batch processing can be used to solve this problem at this time. Of course, there are network restrictions, which are common. Generally, it is troublesome to restrict vpn connection ports, and it is necessary to replace vpn all the time. If the system and network are restricted, you can only contact the network management to remove the restriction. This problem is still difficult to solve.
4. The problem of connecting devices: If all the methods mentioned above in Bian Xiao are tried or useless, it is necessary to consider whether there is a problem with connecting devices. Another way to test this problem is that vpn can be used on other computers, but not on your own computer. It can only be solved from the source. Try to start the local network computer and try network devices including routers to restore the computer to its original network state.