A socket error, such as socket error 10051, occurs any time a computer tries to connect to another network or server. Error 10051 occurs because the other network cannot be reached, usually because there is a problem with the router or modem of the computer trying to connect. This can be as harmless as turning off your router or interfering with a firewall. At the other end of the spectrum, the router may be misconfigured or may have been destroyed and not working.
Socket error 10051 is commonly caused by problems with a router or modem.
Whenever a connection cannot be established, as in the case of socket error 10051, one of the most common culprits is a firewall program. Although designed to keep your computer secure, a firewall can restrict friendly connections. You should disable the firewall and see if the connection can be made. If you still get the socket error, the firewall is not faulty.
If the router or modem is down, there is no way for the computer to connect to another server. Someone may have bricked the router or intended to reset it and never turn it on again. Turning the router back on should reset the Internet server and allow the computer to connect to a server. If the router was damaged by bumping it or spilling it on it, for example, it may need to be replaced entirely.
An incorrectly configured router can cause socket error 10051. An incorrect configuration means that the router believes that it cannot communicate with the server and therefore does not attempt to establish a connection. Some advanced users may encounter the problem, but it’s best to call your ISP and have someone check your router settings. The provider will be able to find the problem and tell the user how to fix it.
Some users have more than one router active at the same time. If there is more than one, one part of the computer may think it needs to communicate with one router, while another part thinks another router should be used. In this case, none of the routers have been designated as the primary router, so neither will work. Configuring the computer to talk to only one router will alleviate this problem.
A similar problem that some users believe can cause socket error 10051 is when the computer is told not to use any routers. This would make the network unreachable, but would throw a different socket error. When the computer does not have a router configured, it returns a socket error 10065.
